Sunday

October 23, 2016
Total # Posts: 2,236

**Pre-Cal**

Use Trigonometric Identities : sin ( x / 2 ) = + OR - sqroot [ ( 1 - cos x ) / 2 ] cos ( x / 2 ) = + OR - sqroot [ ( 1 + cos x ) / 2 ] 0° < x < 90° meen x lies in Quadrant I In Quadrant I sin x and cos x are positive so : sin ( x / 2 ) = sqroot [ ( 1 - cos x ) / ...

*July 7, 2016*

**math**

30 = 8 * sqroot ( h - 40 ) Divide both sides by 8 30 / 8 = sqroot ( h - 40 ) 2 * 15 / ( 2 * 4 ) = sqroot ( h - 40 ) 15 / 4 = sqroot ( h - 40 ) Raise both sides to the power of two : ( 15 / 4 ) ^ 2 = h - 40 225 / 16 = h - 40 Add 40 to both sides 225 / 16 + 40 = h - 40 + 40 225...

*July 6, 2016*

**math**

3 x / 4 - 16 = 44 Add 16 to both sides 3 x / 4 - 16 + 16 = 44 + 16 3 x / 4 = 60 Multiply both sides by 4 3 x = 240 Divide both sides by 3 x = 240 / 3 x = 80 Proof : 3 * 80 / 4 - 16 = 240 / 4 - 16 = 60 - 16 = 44

*July 2, 2016*

**Mathematics**

P ( x ) = x ^ 3 + 2 x ^ 2 - 11 x - 12 This is a polynomial of degree 3. To find zeros for polynomials of degree 3 or higher we use Rational root test. The Rational Root Theorem tells you that if the polynomial has a rational zero then it must be a fraction p / q, where p is a ...

*July 2, 2016*

**math**

W / L = 60 / 80 = 20 * 3 / 20 * 4 = 3 / 4

*July 2, 2016*

**Math**

A = Ama's ages K = Karla's ages D = Daniel's ages Ama is 3 years older than Karla this mean : A = K + 3 Daniel is 2 years older than Ama this mean : D = A + 2 The sum of their ages is 32 this mean : A + K + D = 32 Now you have 3 equatios : A = K + 3 D = A + 2 A + K...

*June 25, 2016*

**Math**

x = 10% = 10 / 100 = 0.1 10% acid solution of 40 mL = 0.1 * 40 mL = 4 mL of acid Volume of new acid solution = 40 mL + x where x = volume of added wather 4 mL represent 4 % 4 % = 4 / 100 = 0.04 Now 4 mL of acid / new volume = 4 % =0.04 4 mL / ( 40 mL + x ) = 0.04 In ...

*June 24, 2016*

**Math**

4 3 / 5 = 4 + 3 / 5 = 4 * 5 / 5 + 3 / 5 = 20 / 5 + 3 / 5 = 23 / 5 ( 2 / 3 ) / 4 3 / 5 = ( 2 / 3 ) / ( 23 / 5 ) = 2 * 5 / ( 3 * 23 ) = 10 / 69 pounds

*June 12, 2016*

**math**

3 ( x - 2 ) ^ 2 - 12 = 0 Divide both sides by 3 3 ( x - 2 ) ^ 2 / 3 - 12 / 3 = 0 / 3 ( x - 2 ) ^ 2 - 4 = 0 Add 4 to both sides ( x - 2 ) ^ 2 - 4 + 4 = 0 + 4 ( x - 2 ) ^ 2 = 4 Take square root of both sides x - 2 = + OR - sqroot ( 4 ) x - 2 = + OR - 2 1 solution : x - 2 = - 2 ...

*June 12, 2016*

**algebra**

Yes. ( x + c ) ^ 2 = x ^ 2 + 2 * x * c + c ^ 2 In this case : 2 x c = 14 x Divide both sides bny 2 x 2 x c / 2 x = 14 x / 2 x c = 7 So : ( x + c ) ^ 2 = x ^ 2 + 2 * x * c + c ^ 2 ( x + 7 ) ^ 2 = x ^ 2 + 2 x * 7 + 7 ^ 2 = x ^ 2 + 14 x + 49

*June 1, 2016*

**algebra 1**

x ^ 8 * 2 y ^ 10 * 5 x ^ 5 = 2 * 5 * x ^ 8 * x ^ 5 * y ^ 10 = 10 x ^ ( 8 + 5 ) * y ^ 10 = 10 x ^ 13 y ^ 10

*June 1, 2016*

**Algebra**

f ( x ) = - x ^ 2 + 5 x + 4 f ( 3 ) = - 3 ^ 2 + 5 * 3 + 4 = - 9 + 15 + 4 = 10 f ( 5 ) = - 5 ^ 2 + 5 * 5 + 4 = - 25 + 25 + 4 = 4 The average rate of change : [ f ( 5 ) - f ( 3 ) ] / ( 5 - 3 ) = ( 10 - 4 ) / ( 5 - 3 ) = 6 / 2 = 3 Answer A

*May 24, 2016*

**Maths (Need Help)**

If y^2-1/4y=0 mean : y ^ 2 - ( 1 / 4 ) y = 0 then : Write y ^ 2 like : 4 y ^ 2 / 4 Now : 4 y ^ 2 / 4 - ( 1 / 4 ) y = 0 ( 1 / 4 ) 4 y - ( 1 / 4 ) y = 0 ( 1 / 4 ) ( 4 y ^ 2 - y ) = 0 ( 1 / 4 ) y ( 4 y - 1 ) = 0 Now you must solwe two equations : ( 1 / 4 ) y = 0 and 4 y - 1 = 0...

*May 24, 2016*

**math**

Go on : calc101.c o m When page be open click option : derivative then in rectangle Take the derivative of type : sin[cos[x^2]] and click option : DO IT You will see solution step by step.

*May 24, 2016*

**Math**

d = Diameter P = Perimeter P = d * pi = 14 * pi 4 P = 4 * 14 * pi = 56 pi = 56 * 3.14159 = 175.92904 in approx. 176 in

*May 24, 2016*

**Math**

Now Rony is 16 years old Sister is 16 / 4 = 4 years old After x years Rony will be 16 + x yeras old Sister will be 4 + x years old Now you must solve equation : ( 16 + x ) / ( 4 + x ) = 2 Multiply both sides by 4 + x 16 + x = 2 ( 4 + x ) 16 + x = 8 + 2 x Subtract 8 to both ...

*May 24, 2016*

**Algebra**

c = children a = adults 2200 people enter the zoo mean : c + a = 2200 $4,550.00 is collected mean : 1.5 c + 4 a = 4550 Now you must solve system: c + a = 2200 1.5 c + 4 a = 4550 c + a = 2200 Subtract c to both sides c + a - c = 2200 - c a = 2200 - c 1.5 c + 4 a = 4550 1.5 c + ...

*May 24, 2016*

**Algebra**

x = 70% alcohol solution y = 30% alcohol solution 120 L of a 45% solution have : 120 * 0.45 = 54 L alcohol Now you must solve system : 0.7 x + 0.3 y = 54 x + y = 120 The solutions are : x = 45 L , y = 75 L Proof : 0.7 * 45 + 0.3 * 75 = 31.5 + 22.5 = 54 L x + y = 45 + 75 = 120 L

*May 20, 2016*

**5th grade math**

1 ft = 12 in 60 / 12 = 5 ft

*May 18, 2016*

**Algebra**

Correct answer. ( a + b ) ^ 2 = a ^ 2 + 2 a b + b ^ 2 In this case : a = 1 2 a b = 9 2 * 1 * b = 9 2 b = 9 Divide both sides by 2 b = 9 / 2 c = b ^ 2 = ( 9 / 2 ) ^ 2 = 81 / 4 ( x + 9 / 2 ) ^ 2 = x ^ 2 + 9 x + ( 81 / 4 )

*May 13, 2016*

**Maths**

y = the width L = the length A = the area of original rectangle A = y * L = 140 y * L = 140 Divide both sides by y L = 140 / y New area : ( y - 2 ) ( L + 3 ) = 136 ( y - 2 ) ( 140 / y + 3 ) = 136 y * 140 / y - 2 * 140 / y + 3 * y - 3 * 2 = 136 140 - 280 / y + 3 y - 6 = 136 - ...

*May 12, 2016*

**Algebra**

( 1 / 2 ) ( k - 5 ) = 3 Multiply both sides by 2 k - 5 = 6 Add 5 to both sides k - 5 + 5 = 6 + 5 k = 11 Proof : ( 1 / 2 ) ( k - 5 ) = ( 1 / 2 ) ( 11 - 5 ) = 6 / 2 = 3

*May 10, 2016*

**College Math**

x = 3 -inch bolts y = 4 -inch bolts James bought 24 bolts. This mean x + y = 24 36 cents = $ 0.36 42 cents = $ 0.42 Total price = $ 9 This mean : 0.36 x + 0.42 y = 9 Now you must solve system : x + y = 24 0.36 x + 0.42 y = 9 Try.

*May 6, 2016*

**Math**

17 85 : 51 = 17 * 5 : ( 17 * 3 ) = 5 : 3

*May 5, 2016*

**Geometry (Help)**

12 cm / 4 cm = 3 16 cm / 4 cm = 4 8 cm / 4 cm = 2 3 * 4 * 2 = 24 balls

*May 4, 2016*

**Algebra 1**

90 gallons of a 23% salt water = 90 * 23 / 100 = 2070 /100 = 20.7 gallons of salt. x = quantity of salt wather y = quantity of fresh wather Fresh wather have 0 % salt. This mean all salt come on 30 % salt wather. Quantity of salt in 30 % salt wather = 0.3 x 0.3 x = 20.7 Divide...

*May 4, 2016*

**MATH HELP ASAP**

In a Geometric Sequence each term is found by multiplying the previous term by a constant. In this case constant = 0.5 Geometric Sequence

*May 4, 2016*

**MATH HELP ASAP**

1.6 * 0.5 = 0.8 0.8 * 0.5 = 0.4 0.4 * 0.5 = 0.2 What do you think that is?

*May 4, 2016*

**math**

1 3/8 = 1 + 3 / 8 = 8 / 8 + 3 / 8 = 11 / 8 ( 1 3/8 ) / ( 5 / 8 ) = ( 11 / 8 ) / ( 5 / 8 ) = ( 8 * 11 ) / ( 8 * 5 ) = 11 / 5 = 10 / 5 + 1 / 5 = 2 + 1 / 5 = 2 1/5 = 2.2

*May 4, 2016*

**MATH HELP ASAP**

If you think on 4,8,12,16,... then : an = 4 n a20 = 4 *20 = 80

*May 4, 2016*

**MATH HELP ASAP**

Which expression?

*May 4, 2016*

**algebra**

4 * 1 = 4 4 * 2 = 8 4 * 3 = 12 4 * 4 = 16 etc. a. 4n

*May 4, 2016*

**alegbra help asap**

2n + 3 2 * 1 + 3 = 2 + 3 = 5 2 * 2 + 3 = 4 + 3 = 7 2 * 3 + 3 = 6 + 3 = 9 2 * 4 + 3 = 8 + 3 = 11 5 , 7 , 9 , 11 Answer c.

*May 4, 2016*

**PLEASE HELP ASAP ALGEBRA**

In an Arithmetic Sequence the difference between one term and the next is a constant, so : 3 - 4.5 = - 1.5 4.5 - 6 = - 1.5 6 - 7.5 = - 1.5 The difference is a constant, so : a. arithmetic sequence

*May 4, 2016*

**algebra**

The area of a triangle is always half the product of the base and height. In this case the base : b = c + 2 A = b * h / 2 A = ( c + 2 ) * h / 2 The area is ( 2 c ^ 3 + 16 ) so: 2 c ^ 3 + 16 = ( c + 2 ) * h / 2 Multiply both sides by 2 4 c ^ 3 + 32 = ( c + 2 ) * h Divide both ...

*May 4, 2016*

**Math**

3 x ^ 2 = 0 Divide both sides by 3 3 x ^ 2 / 3 = 0 / 3 x ^ 2 = 0 x = sqroot ( 0 ) = 0

*May 3, 2016*

**Math**

a = apples cost o = orange cost 70 cents = 0.7 $ An orange cost 70 cents less than an apple. This mean : o = a - 0.7 $ Total cost = 41.6 $ 8 a * 10 o = 41.6 8 a + 10 ( a - 0.7 ) = 41.6 8 a + 10 a - 7 = 41.6 18 a - 7 = 41.6 Add 7 to both sides 18 a - 7 + 7 = 41.6 + 7 18 a = 48....

*May 3, 2016*

**algebra 2**

2 x + 6 y = 16 Multiply both sides by 2 4 x + 5 y = 11 - 4 x + 12 y = 32 ________________ 4 x - 4 x + 5 y - 12 y = 11 - 32 - 7 y = - 21 Divide both sides by - 7 y = - 21 / - 7 y = 3 Replace value of y in equation : 4 x + 12 y = 32 4 x + 12 * 3 = 32 4 x + 36 = 32 Subtract 36 to...

*May 3, 2016*

**Maths**

x = a number x + x / 2 = 6 2 x / 2 + x / 2 = 6 3 x / 2 = 6 Multiply both sides by 2 3 x = 12 Divide both sides by 3 x = 12 / 3 = 4 Proof ; 4 / 2 + 4 = 2 + 4 = 6

*April 26, 2016*

**math**

p1 = paper 1 p2 = paper 2 p3 = paper 3 p4 = paper 4 ( a ) The mean of the first three papers Jenny has sat is 72%. ( p1 + p2 + p3 ) / 3 = 72 % Multiply both sides by 3 p1 + p2 + p3 = 72 % * 3 = p1 + p2 + p3 = 216 % After 4 papres mean is : ( p1 + p2 + p3 + p4 ) / 4 If she ...

*April 26, 2016*

**Algebra I DONT KNOW HOW TO DO 3 VARIABLES**

x + y + 5 z = 2 4 x - 3 y + 5 z = 3 3 x - 2 y + 5 z = 1 All three equations contain member 5 z Equation ( 1 ) x + y + 5 z = 2 Subtract ( x + y ) to both sides x + y + 5 z - ( x + y ) = 2 -( x + y ) 5 z = 2 - x - y Equation ( 2 ) 4 x - 3 y + 5 z = 3 Subtract ( 4 x - 3 y ) to ...

*April 25, 2016*

**Ratios!!!!**

Remark : 1 * ( x - 3 ) : ( 3 x - 2 ) = ( x - 3 ) : ( 3 x - 2 ) 4 / 4 = 1 so : ( 4 / 4 ) * ( x - 3 ) : ( 3 x - 2 ) 4 * ( x - 3 ) : [ 4 * ( 3 x - 2 ) ] = ( 4 x - 12 ) : ( 12 x - 8 ) Question 10 Answers B and D

*April 21, 2016*

**Ratios!!!!**

8. A = Abby's part I = Ingrid's part J = John's part There are sixty three candies in the bag. This mean: A + I + J = 63 A / I / J = 2 / 3 / 4 This mean : A / I = 2 / 3 I / J = 3 / 4 so: A / I = 2 / 3 Multiply both sides by I A = 2 I / 3 A = ( 2 / 3 ) I I / J = 3...

*April 21, 2016*

**Math**

B = Bill's money S = Sammy's money M = Mary's money J = James's money Sammy has 15 $ more than Billy. S = B + 15 Mary has twice as much as Sammy. M = 2 S = 2 ( B + 15 ) = 2 B + 2 * 15 = 2 B + 30 James has 5 $ less than Mary. J = M - 5 = 2 B + 30 - 5 = 2 B + 25 ...

*April 18, 2016*

**Math**

a = First number b = Second number The difference between two numbers is 6. This mean : a - b = 6 Their product is 2016. This mean : a * b = 2016 Now : a - b = 6 Add b to both sides a - b + b = 6 + b a = 6 + b a = b + 6 Replace this value in expression : a * b = 2016 ( b + 6...

*April 18, 2016*

**math**

cot x = cos x / sin x sec x = 1 / cos x cot x * sec x = ( cos x / sin x ) * ( 1 / cos x ) = 1 / sin x = csc x

*April 18, 2016*

**Maths**

a = the smaller number b = the larger number The product of two natural numbers is 18. This mean : a * b = 18 If one is added to four times the smaller number this is equal to the larger number. This mean : 1 + 4 a = b So : b = 1 + 4 a Replace this value in expression : a * b...

*April 18, 2016*

**Math Trig**

Correct answer but you also can write : cos ( 2 u ) = cos ^ 2 ( u ) - sin ^ 2 u In this case : sin ( u ) = 5 / 13 sin ^ 2 ( u ) = ( 5 / 13 ) ^ 2 = 25 / 169 cos ^ 2 ( u ) = 1 - sin ^ 2 ( u ) = 1 - 25 / 169 = 169 / 169 - 25 / 169 = 144 / 169 cos ( 2 u ) = cos ^ 2 ( u ) - sin ^ 2...

*April 14, 2016*

**Math**

Correct answer becouse : ( 0.0015 / 0.45 ) * 100 % = 0.003333 * 100 % = 0.3333 %

*April 14, 2016*

**Math**

sin theta = + OR - sqroot ( 1 - cos ^ 2 theta ) tan theta = sin theta / cos theta tan theta = + OR - sqroot ( 1 - cos ^ 2 theta ) / cos theta In Quadrant IV tangent are negative so : tan theta = - sqroot ( 1 - cos ^ 2 theata ) / cos theta

*April 14, 2016*

**math**

sqrt ( 4 / 32 ) = sqrt [ 4 / ( 4 * 8 ) ] = sqrt ( 1 / 8 ) = sqrt [ 1 / ( 4 * 2 ) ] = sqrt ( 1 ) / [ sqrt ( 4 ) * sqrt ( 2 ) ] = 1 / 2 sqrt ( 2 ) 2 pi sqrt ( 4 / 32 ) = 2 pi * 1 / 2 sqrt ( 2 ) = pi / sqrt ( 2 ) = _________________________________ Remark: sqrt ( 2 ) = 2 ^ ( 1 / ...

*April 14, 2016*

**math**

In quadratic equation: a x ^ 2 + b x + c value D = b ^ 2 - 4ac is called the discriminant. When Discriminant is zero we get just one real solution. p x ^ 2 - 12 x + 4 = 0 In this case : a = p , b = - 12 , c = 4 D = b ^ 2 - 4 a c = ( - 12 ) ^ 2 - 4 * p * 4 = 144 - 16 p = 0 Add ...

*April 14, 2016*

**problem solving**

S = Susan's age R = Ritas's age Susan is 4 years older than her sister Rita. This mean : S = R + 4 Seven years ago Susan was ( S - 7 ) yrs old, and Rita was ( R - 7 ) yrs old. Seven years ago, Susan was twice as old as Rita. This mean : ( S - 7 ) / ( R - 7 ) = 2 ...

*April 10, 2016*

**Trigonometrt**

a. 810 ° = 720 ° + 90 ° = 2 * 360 ° + 90 ° So : sin ( 810 ° - theta ) = sin ( 90 ° - theta ) sin ( A - B ) = sin A * cos B - cos A * sin B In this case A = 90 ° , B = theta. sin 90 ° = 1 cos 90 ° = 0 sin ( 90 ° - theta ) = sin 90 &...

*April 9, 2016*

**Algebra**

x + 2 y = 10 Subtract x to both sides x + 2 y - x = 10 - x 2 y = 10 - x Divide both sides by 2 2 y / 2 = 10 / 2 - x / 2 y = 5 - x / 2 x ^ 2 + y ^ 2 = 25 x ^ 2 + ( 5 - x / 2 ) ^ 2 = 25 ________________________________ Remark: ( a - b ) ^ 2 = a ^ 2 - 2 * a * b + b ^ 2 ...

*April 6, 2016*

**math**

( - 8 ) * ( - 7 ) = ( - 1 * 8 ) * ( - 1 * 7 ) = ( - 1 ) * ( - 1 ) * 8 * 7 = 1 * 8 * 7 = 1 * 56 = 56

*April 5, 2016*

**Algebra 1**

a = larger number b = smaller number One third the sum of two numbers is 10. This mean: ( a + b ) / 3 = 10 Multiply both sides by 3 a + b = 30 Half the difference is 14. This mean: ( a - b ) / 2 = 14 Multiply both sides by 2 a - b = 28 Add b to both sides a - b + b = 28 + b a...

*April 5, 2016*

**Algebra**

4 x - 6 y - 3 = 7 x + 2 y - 4 Subtract 4 x to both sides 4 x - 6 y - 3 - 4 x = 7 x + 2 y - 4 - 4 x - 6 y - 3 = 3 x + 2 y - 4 Add 3 to both sides - 6 y - 3 + 3 = 3 x + 2 y - 4 + 3 - 6 y = 3 x + 2 y - 1 Subtract 2 y to both sides - 6 y - 2 y = 3 x + 2 y - 1 - 2 y - 8 y = 3 x - 1...

*April 5, 2016*

**maths**

( 14 / 40 ) * 100 % = 0.35 * 100 % = 35 %

*April 5, 2016*

**Math**

1 ft = 12 in 2 ft = 24 in r = 24 in = 2 ft The volume of a ball: V = ( 4 / 3 ) * pi * r ^ 3 = ( 4 * pi / 3 ) * 2 ^ 3 = ( 4 * 3.1416 / 3 ) * 2 ^ 3 = ( 12.5664 / 3 ) * 2 ^ 3 = 4.1888 * 2 ^ 3 = 4.1888 * 8 = = 33.5104 ft ^ 3

*April 5, 2016*

**math**

3 / 27 = 3 / ( 3 * 9 ) = 1 / 9 3 / 27 = 10 / x 1 / 9 = 10 / x Multiply both sides by 9 1 = 90 / x Multiply both sides by x x = 90 min OR x = ( 10 miles / 3 miles ) * 27 min = ( 10 / 3 ) * 27 min = 270 min / 3 = 90 min

*April 5, 2016*

**Social studies**

Ms.Sue Iam from Sarajevo, Bosnia and Herzegovina, former Yugoslavia citizen. YUGOSLAVIA WAS NEVER HAD SOVIET RULE. It was very different from the socialism of the Soviet.

*March 30, 2016*

**pr calc 11**

The numbers are: 8 an - 5 becouse: 8 * ( - 5 ) = - 40 and 8 - 5 = 3 x ^ 2 + 3 x - 40 = ( x + 8 ) ( x - 5 )

*March 30, 2016*

**pr calc 11**

( a + b ) ^ 2 = a ^ 2 + 2 a b + b ^ 2 so: ( x + 2 ) ^ 2 = x ^ 2 + 2 x * 2 + 2 ^ 2 = x ^ 2 + 4 x + 4 ( x + 2 ) ^ 2 - ( x + 2 ) - 42 = x ^ 2 + 4 x + 4 - x - 2 - 42 = x ^ 2 + 4 x + 4 - x - 44 = x ^ 2 + 4 x - x + 4 - 44 = x ^ 2 + 3 x - 40 Find two numbers whose product is - 40 and...

*March 30, 2016*

**Math**

Parabola - 5 t ^ 2 - 25 t is concave downward. That's why you get negative time. You can switch - 5 to 5. If you want to see graph go on: w o l f r a m a l p h a . c o m When page be open in rectangle type: - 5 t ^ 2 - 25 t , t = 0 to - 5 and click option: = You wil see ...

*March 29, 2016*

**math**

x = 0.6969... 100 x = 0.6969... * 100 = 69.6969... 100 x - x = 99 x = 69.6969... - 0.6969... = 69 99 x = 69 3 * 33 x = 3 * 23 Divide both sides by 3 33 x = 23 Divide both sides by 33 x = 23 / 33 0.6969... = 23 / 33

*March 24, 2016*

**math**

1 / 2 (14 x - 2 ) - 1 / 4 ( - 4 x - 24 ) = 14 x / 2 - 2 / 2 - ( - 4 x / 4 ) - ( - 24 / 4 ) = 14 x / 2 - 2 / 2 + ( 4 x / 4 ) + ( 24 / 4 ) = 7 x - 1 + x + 6 = 8 x + 5

*March 24, 2016*

**Math**

In google type: integration by parts online emathelp When you see list of results cilck on: Integral (Antiderivative) Calculator with Steps - eMathHelp When page be open in rectangle type: e^(3x) sin (2x) then clic option: CALCULATE You wil see solution step-by-step.

*March 24, 2016*

**algebra i**

You can square rooted only expresiion between brackets, not single number.

*March 21, 2016*

**algebra i**

( x - 4 ) ^ 2 = 625 Take square root to both sides + OR - ( x - 4 ) = 25 1 solution: x - 4 = 25 Add 4 to both sides x - 4 + 4 = 25 + 4 x = 29 2 solution: - ( x - 4 ) = 25 - x + 4 = 25 Subtract 4 to both sides - x + 4 - 4 = 25 - 4 - x = 21 Multiply both sides by - 1 x = - 21 ...

*March 21, 2016*

**Math haha**

7 / 2 = ( 7 / 2 ) * ( 3 / 3 ) = 21 / 6 ( 7 / 2 + 5 / 6 ) ^ 2 - ( 7 / 2 - 5 / 6 ) ^ 2 = ( 21 / 6 + 5 / 6 ) ^ 2 - ( 21 / 6 - 5 / 6 ) ^ 2 = ( 26 / 6 ) ^ 2 - ( 16 / 6 ) ^ 2 = 676 / 36 - 256 / 36 = ( 676 - 256 ) / 36 = 420 / 36 = ( 12 * 35 ) / ( 12 * 3 ) = 35 / 3

*March 20, 2016*

**Math-Measure's & area**

1. A = B * H = 82 * 16.6 = 1,361.2 2. 0.123333.... is a rational number becouse : 0.123333... = 37 / 300

*March 17, 2016*

**Math**

Rectangular pyramid

*March 17, 2016*

**algebra**

OR x + 9 y = 77 Multiply both sides by 7 7 * x + 9 y * 7 = 77 * 7 7 x + 63 y = 539 - 7 x - y = 27 _______________ 7 x - 7 x + 63 y - ( - y ) = 539 - 27 0 + 63 y + y = 512 64 y = 512 y = 512 / 64 = 8 x + 9 y = 77 x + 9 * 8 = 77 x + 72 = 77 Subtract 72 to both sides x + 72 - 72...

*March 13, 2016*

**algebra**

7 x - y = 27 Divide both sides by 7 7 x / 7 - y / 7 = 27 / 7 x - y / 7 = 27 / 7 x + 9 y = 77 x + 9 y * 7 / 7 = 77 * 7 / 7 x + 63 y / 7 = 539 / 7 Subtract x - y / 7 = 27 / 7 from equation x + 63 y / 7 = 539 / 7 x + 63 y / 7 = 539 / 7 - x - y / 7 = 27 / 7 ...

*March 13, 2016*

**Math**

Numbers 1 ÷ 9 are one digits numbers. Numbers 10 ÷ 30 are two digits numbers. Obviously Eric will write 9 one digits numbers and 21 two digits numbers. 9 * 1 + 21 * 2 = 9 + 42 = 51 digits

*March 9, 2016*

**Math**

55 = 11 * 5

*March 8, 2016*

**Math**

You can write original number as : x = 10 a + b Reverse number you can write as : y = 10 b + a x + y = 10 a + b + 10 b + a = 11 a + 11 b = 11 ( a + b ) Example : Original number: x = 23 a = 2 , b = 3 x = 10 a + b = 10 * 2 + 3 = 20 + 3 = 23 Reverse number: y = 10 b + a = 10 * 3...

*March 8, 2016*

**database**

Find answer on wikipedia.

*March 8, 2016*

**maths**

x = 0.27272727... 100 x = 100 * 0.27272727... 100 x = 27.27272727... 100 x - x = 99 x = 27.27272727... - 0.27272727... = 27 99 x = 27 9 * 11 x = 9 * 3 Divide both sides by 9 11 x = 3 Divide both sides by 11 x = 3 / 11

*March 7, 2016*

**Math**

A golden rectangle is a rectangle whose side lengths are in the golden ratio: phi = 1 / [ ( 1 + sqroot 5 ) / 2 ] W = L * phi W = 12 * 1 / [ ( 1 + sqroot 5 ) / 2 ] = 12 * 2 / ( 1 + sqroot 5 ) = 24 / ( 1 + sqroot 5 ) = 24 / ( 1 + 2.236068 ) = 24 / 3.236068 = 7.416408 ft W = 7.4 ...

*March 7, 2016*

**Math**

x ^ 2 + 10 = 7 x Subtract 7 x to both sides x ^ 2 + 10 - 7 x = 7 x - 7 x x ^ 2 - 7 x + 10 = 0 Now you must solve this quadratic equation. The solutions are : x = 2 and x = 5 Proof : 2 ^ 2 + 10 = 4 + 10 = 14 = 7 * 2 5 ^ 2 + 10 = 25 + 10 = 35 = 7 * 5

*March 6, 2016*

**math**

x1 = score math = 65 x2 = score arts = 86 x3 = score science = 84 x4 = score social studies = 78 x5 = score grammar average = ( x1 + x2 + x3 + x4 + x5 ) / 5 = 80 ( 65 + 86 + 84 + 78 + x5 ) / 5 = 80 ( 313 + x5 ) / 5 = 80 Multiply both sides by 5 313 + x5 = 80 * 5 313 + x5 = 400...

*March 5, 2016*

**Maths**

Copy your question in google. You will find answer.

*March 5, 2016*

**math**

(e ^ 3 / f ^ 2 ) ^ - 3 = 1 / (e ^ 3 / f ^ 2 ) ^ 3 = 1 / ( e ^ 9 / f ^ 6 ) = f ^ 6 / e ^ 9 ( e ^ - 4 / f ) ^ - 1 = 1 / [ ( 1 / e ^ 4 ) / f ] = 1 / [ 1 / ( e ^ 4 * f ) ] = e ^ 4 * f / 1 = e ^ 4 * f (e ^ 3 / f ^ 2 ) ^ - 3 * ( e ^ - 4 / f ) ^ - 1 = ( f ^ 6 / e ^ 9 ) * e ^ 4 * f = ...

*February 21, 2016*

**Algebra**

Yes y = 3 x + 7 = 4 * 7 = 28 3 x + 7 = 28 3 x = 28 - 7 = 21 x = 21 / 3 = 7 yrs 7 ft + 7 * 3 ft = 7 ft + 21 ft = 28 ft = 4 * 7 ft

*February 21, 2016*

**Math Help!**

6 - ( - 3 ) = 9 15 - 6 = 9 24 - 15 = 9 33 - 24 = 9 42 - 33 = 9 51 - 42 = 9 - 3 ,6 ,15 , 24 , 33 , 42 , 51 Arithmetic progression. Initial term a1 = - 3 Common difference d = 9

*February 17, 2016*

**PLZ HELP MATH**

p = pressure d = depth p = 14.7 + 14.7 ( d / 30 ) = 14.7 ( 1 + d / 30 ) In this case d = 1000 ft p = 14.7 ( 1 + 1000 / 30 ) = 14.7 ( 1 + 33.33 ) = 14.7 * 34.33 = 504.7 psi

*February 14, 2016*

**Algebra ASAP**

x ^ - 2 = 1 / x ^ 2 ( 6 x ^ - 2 ) ^ 2 = ( 6 / x ^ 2 ) ^ 2 = 6 ^ 2 / ( x ^ 2 ) ^ 2 = 36 / x ^ 4 ( 0.5 x ) ^ 4 = 0.5 ^ 4 * x ^ 4 = 0.0625 x ^ 4 ( 6 x ^ - 2 ) ^ 2 0.5 x ^ 4 = ( 36 / x ^ 4 ) * 0.0625 x ^ 4 = 36 * 0.0625 * x ^ 4 / x ^ 4 = 36 * 0.0625 = 2.25

*February 14, 2016*

**Math**

Probability that the 7th grader is a boy = number of boys/number of students = 3 / ( 3 + 3 ) = 3 / 6 = 1 / 2 Probability that the 8th grader is a boy = number of boys/number of students = 1 /( 4 + 1 ) = 1 /5 Probability that both are boys = 1 / 2 * ( 1 / 5 ) = 1 / 10 = 0.1 = 10 %

*February 14, 2016*

**math**

a1 = first number a2 = second number a3 = third number a2 = a1 + 2 a3 = a2 + 2 = a1 + 2 + 2 = a1 + 4 a1 + a2 + a3 = a1 + a1 + 2 + a1 + 4 = 3 a1 + 6 = 147 Subtract 6 to both sides 3 a1 + 6 - 6 = 147 - 6 3 a1 = 141 Divide both sides by 3 a1 = 141 / 3 = 47 a1 = 47 a2 = 47 + 2 = ...

*February 13, 2016*

**math**

n = Number of nickels q = Number of quarters He has 10 more nickels than quarters mean : n = q + 10 Justin has a total of 50 coins that are all nickels and quarters mean : n + q = 50 n = q + 10 so : n + q = 50 q + 10 + q = 50 2 q + 10 = 50 Subtract 10 to both sides 2 q + 10 - ...

*February 10, 2016*

**Algebra**

94 % = 94 / 100 = 0.94 $ 560,000 / 0.94 = $ 595744.68

*February 9, 2016*

**Math**

L = Lita's age J = Joe's age Lita is three times Joe's age mean : L = 3 J The difference of their ages is 10 mean : L - J = 10 L = 3 J so : L - J = 10 3 J - J = 10 2 J = 10 Divide both sides by 2 J = 10 / 2 = 5 L = 3 J = 3 * 5 = 15 Lita's present ages = 15 Joe...

*February 9, 2016*

**algebra equations**

x = a number 4 less than 5 times itself mean : 5 x - 4 x + 5 x - 4 = 27 6 x - 4 = 27 Add 4 to both sides 6 x - 4 + 4 = 27 + 4 6 x = 31 Divide both sides by 6 x = 31 / 6 Are you shure that the result is 27?

*February 9, 2016*

**math**

6 / 27 = 3 * 2 / ( 3 * 9 ) = 2 / 9

*February 6, 2016*

**Algebra**

4. 3 ( 4 - 2 x ) = - 2 x 3 * 4 - 3 * 2 x = - 2 x 12 - 6 x = - 2 x Add 6 x to both sides 12 - 6 x + 6 x = - 2 x + 6 x 12 = 4 x Divide both sides by 4 3 = x x = 3 Answer d 5. 5.4 + 0.2 x = - 1.4 x + 8.6 Subtract 5.4 to both sides 5.4 - 5.4 + 0.2 x = - 1.4 x + 8.6 - 5.4 0.2 x...

*February 1, 2016*

**math**

8 / 270 = x / 72.5 Multiply both sides by 72.5 72.5 * 8 / 270 = x 580 / 270 = x 2.148148 = x x = 2.148148 x = 2.1 fluid ounces Rounded to the nearest tenth.

*January 30, 2016*

**Math**

Substitute the values a = 4 , b = - 9 , c = - 9 into the quadratic formula x1/2 = [ - b +OR- sqroot( b ^ 2 - 4 a c ) ] / 2 a x1/2 = [ - ( - 9 ) +OR- sqroot( ( - 9 ) ^ 2 - 4 * 4 * ( - 9 ) ) ] / 2 * 4 x1/2 = [ 9 +OR- sqroot( 81 - 4 * ( - 36) ) ] / 8 x1/2 = [ 9 +OR- sqrt ( 81 + ...

*January 29, 2016*

**Math**

1 / 4 = 1 * 8 / ( 4 * 8 ) = 8 / 32 5 * 16 = 5 * 2 / ( 16 * 2 ) = 10 / 32 Your answer is correct.

*January 26, 2016*