Friday

April 29, 2016
Total # Posts: 2,098

**Precalculus**

cos ^ 2 ( x ) - sin ^ 2 ( x ) = 2 cos ^ 2 ( x ) - 1 Subtract cos ^ 2 ( x ) to both sides cos ^ 2 ( x ) - sin ^ 2 ( x ) - cos ^ 2 ( x ) = 2 cos ^ 2 ( x ) - 1 - cos ^ 2 ( x ) - sin ^ 2 ( x ) = cos ^ 2 ( x ) - 1 Add 1 to both sides - sin ^ 2 ( x ) + 1 = cos ^ 2 ( x ) - 1 + 1 1 - ...
*April 3, 2013*

**math**

( 6 p + 4 q ) ( - 2 p + 9 q ) = 6 p * ( - 2 p ) + 4 q * ( - 2 p ) + 6 p * 9 q + 4 q * 9 q = - 12 p ^ 2 - 8 p q + 54 p q + 36 q ^ 2 = - 12 p ^ 2 + 46 p q + 36 q ^ 2
*April 3, 2013*

**Roman Numerals**

1. XVIII = 18 XXII = 22 XVIII + XXII = 40 = XL 2. VI = 6 XIX = 19 VI +XIX = 6 + 9 = 25 = XXV 3. M = 1000 CC = 200 M - CC = 1000 - 200 = 800 = DCCC 4. LXXXIV = 84 XLII = 42 LXXXIV - XLII = 84 - 42 = 42 = XLII 5. VI = 6 XI = 11 VI x XI = 6 * 11 = 66 = LXVI 6. X = 10 V = 5 I = 1 ...
*April 3, 2013*

**Math**

1. 8 = 40 / 5 8 2 / 5 = 40 / 5 + 2 / 5 = 42 / 5 Answer a. 2. 3 / 5 = 0.6 2 / 3 = 0.666 You must find number between 0.6 and 0.666 3 / 6 = 1 / 2 = 0.5 3 / 4 = 0.75 5 / 8 = 0.625 7 / 10 = 0.7 Ansver c.
*April 3, 2013*

**geometry**

Rectangles, squares and rhombuses
*April 3, 2013*

**Alg 1**

L = Length W = Width L / W = ( 1 + sqrt 5 ) / 2 Reciprocally : W / L = 1 / [ ( 1 + sqrt 5 ) / 2 ] W / L = 2 / [ ( 1 + sqrt 5 ) ] Multiply both sides by L W = 2 L / 2 / [ ( 1 + sqrt 5 ) ] W = 2 * 32 / [ ( 1 + sqrt 5 ) ] W = 64 / [ ( 1 + sqrt 5 ) ]
*April 3, 2013*

**math**

0.06 % = 0.0 6 / 100 = 6 / 10,000 250 * 0.06 % = 250 * 6 / 10,000 = 1,500 / 10,000 = 0.15 OR 250 * 0.06 / 100 = 15 / 100 = 0.15
*April 1, 2013*

**math**

Correction : 6 / 10 + 7 / 12 = 36 / 60 + 35 / 60
*March 30, 2013*

**math**

60 = 6 * 10 60 = 5 * 12 6 / 10 = 6 * 6 / ( 6 * 10 ) = 36 / 60 7 / 12 = 7 * 5 ( 5 * 12 ) = 35 / 60 6 / 10 + 7 / 12 = 36 / 60 + 25 / 60 = 71 / 60 = ( 60 + 11 ) / 60 = 60 / 60 + 11 / 60 = 1 11 / 60 6 / 10 + 7 / 12 = 71 / 60 = 1 11 / 60
*March 30, 2013*

**Math 0098**

a = first number b = second number c = thirdt number b = 3 c a = c - 7 a + b + c = 113 c - 7 + 3 c + c = 113 5 c = 113 + 7 5 c = 120 c = 120 / 5 c = 24 a = c - 7 = 24 - 7 = 17 b = 3 c = 3 * 24 = 72 first number = 17 b = 72 c = 24 17 + 72 + 24 = 113
*March 29, 2013*

**maths**

( 2 ^ n + 2 ^ ( n - 1 ) ) / ( 2 ^ ( n + 1 ) - 2 ^ n ) Multiply both sides by ( 2 ^ ( n + 1 ) - 2 ^ n ) ________________________________________ ( 2 ^ n ) * 2 ^ ( n + 1 ) = 2 ^ ( 2 n + 1 ) 2 ^ ( n - 1 ) * (2 ^ ( n + 1 ) ) = 2 ^ 2 n 2 ^ ( 2 n + 1 ) + 2 ^ 2 n = 3 * 4 ^ n 2 ^ ( 2 ...
*March 29, 2013*

**college algebra**

Squaring both sides 3 x + 7 = ( 3 x + 5 ) ^ 2 3 x + 7 = 9 x ^ 2 + 2 * 3 x * 5 + 5 ^ 2 3 x + 7 = 9 x ^ 2 + 30 x + 25 0 = 9 x ^ 2 + 30 x + 25 - 3 x - 7 9 x ^ 2 + 27 x + 18 = 0 Divide both sides by 9 x ^ 2 + 3 x + 2 = 0 If you don't know how to solve this equation then in ...
*March 27, 2013*

**Algebra**

5 / ( 2 - i ) Multiply Numerator and Denominator by 2 + i 5 ( 2 + i ) / ( ( 2 - i ) ( 2 + i ) ) = 5 ( 2 + i ) / ( 4 - 2 i + 2 i - i ^ 2 ) = 5 ( 2 + i ) / ( ( 4 - ( - 1 ) ) = 5 ( 2 + i ) / ( 4 + 1 ) = 5 ( 2 + i ) / 5 = 2 + i 5 / ( 2 - i ) = 2 + i
*March 26, 2013*

**Math-Population Word Problem**

a ) Now t = 0 8,600 + 650 ln( t + 1 ) = 8,600 + 650 ln( 0 + 1 )= 8,600 + 650 ln ( 1 ) = 8,600 + 650 * 0 = 8,600 + 0 = 8,600 b ) 8,600 + 650 ln( t + 1 ) = 12,000 650 ln( t + 1 ) = 12,000 - 8,600 650 ln( t + 1 ) = 3,400 ln( t + 1 )= 3,400 / 650 ln( t + 1 )= 5.23076923 t + 1 = e...
*March 26, 2013*

**math**

OR 3 / 16
*March 26, 2013*

**math**

9 / 48
*March 26, 2013*

**algebra**

Slope-Intercept Form: 5 x + 2 y = 8 Subtract 5 x to both sides 5 x + 2 y - 5 x = 8 - 5 x 2 y = - 5 x + 8 Divide both sides by 2 y = - 5 x / 2 + 4 For graph : In google type: functions graphs online When you see list of results click on: rechneronline.de/function-graphs/ When ...
*March 26, 2013*

**geometry**

d = sqrt [ ( x2 - x1 ) ^ 2 + ( y2 - y1 ) ^ 2 ]
*March 25, 2013*

**math**

When you type : abs(x-1)+2 you must click option : Draw
*March 25, 2013*

**math**

In google type: functions graphs online When you see list of results click on: rechneronline.de/function-graphs/ When page be open in blue recatacangle type: abs(x-1)+2 you will see graph The domain of definition or simply the domain of a function is the set of "input&...
*March 25, 2013*

**ap calculas**

In google type : derivative online When you see list of results click on : Wolfram|Alpha Widgets: "Derivative Solver" - Free Mathematics Widget When page be open in rectangele " derivative of " type : (-x^3+3)(3x+2)^3 and click option : Submit When you see ...
*March 25, 2013*

**Algebra 2**

a ^ 2 - b ^ 2 = ( a + b ) ( a - b ) 1 / 81 - 1 / x ^ 2 = ( 1 / 9 ) ^ 2 - ( 1 / x ) ^ 2 = ( 1 / 9 + 1 / x ) ( 1 / 9 - 1 / x ) ( 1 / 9 - 1 / x ) / ( 1 / 81 - 1 /x ^ 2 ) = ( 1 / 9 - 1 / x ) / [ ( 1 / 9 + 1 / x ) ( 1 / 9 - 1 / x ) ] = 1 / ( 1 / 9 + 1 / x ) = 1 / [ ( x + 9 ) / 9 x...
*March 24, 2013*

**math**

- 10 k + ( - 4 m ) - 8 k + 2 m = - 10 k - 4 m - 8 k + 2 m = - 18 k - 2 m = 2 ( - 9 k - m ) = - 2 ( 9 k + m )
*March 21, 2013*

**math**

6 - 4 t = 2 ( 3 - 2 t ) = 2 ( - 2 t + 3 ) = - 2 ( 2 t - 3 )
*March 21, 2013*

**math**

P = 3 a a = P / 3 = ( 15 x + 18 ) / 3 = 5 x + 6
*March 21, 2013*

**Algebra**

1-th term ( n = 1 ) : 3 n + 5 = 3 * 1 + 5 = 3 + 5 = 8 2-th term ( n = 2 ) : 3 n + 5 = 3 * 2 + 5 = 6 + 5 = 11 3-th term ( n = 3 ) : 3 n + 5 = 3 * 3 + 5 = 9 + 5 = 14 4-th term ( n = 4 ) : 3 n + 5 = 3 * 4 + 5 = 12 + 5 = 17 8 , 11 , 14 , 17 Answer B
*March 21, 2013*

**Algebra**

f ( x ) mean : " f is a function of x " f ( 1.5 ) are value of FUNCTION 3 x - 2 when x = 1.5 so of f ( 1.5 ) = 2.5
*March 21, 2013*

**Algebra**

f ( 1.5 ) = 3 * 1.5 - 2 = 4.5 - 2 = 2.5 Answer : A
*March 21, 2013*

**Math,6th grade**

34 * 5 / 2 = 170 / 2 = 85 mi
*March 21, 2013*

**Math**

2 ( 3 + 4 y + 7 ) = 2 * 3 + 2 * 4 y + 2 * 7 = 6 + 8 y + 14 = 8 y + 20
*March 21, 2013*

**algebra**

x ^ 3 - 48 x - 128 = ( x - 8 ) ( x + 4 ) ^ 2 Solutions : x = - 4 and x = 8 x ^ 3 - 12 x + 16 = ( x - 2 ) ^ 2 ( x + 4 ) Solutions : x = - 4 and x = 2
*March 21, 2013*

**math**

sqrt ( - 169 ) = sqrt [ 169 * ( - 1 ) ] = sqrt ( 169 ) sqrt ( - 1 ) = 13 i
*March 21, 2013*

**math**

If 3m 66m mean 3 m 66 cm then: 3 m 66 cm = 3.66 m L = Longer piece S = Shorter piece L = 2 S L + S = 3.66 m 2 S + S = 3.66 m 3 S = 3.66 m Divide both sides by 3 S = 3.66 m / 3 S = 1.22 m = 1 m 22 cm L = 2 S = 2 * 1.22 m = 2.44 m = 2 m 44 cm
*March 20, 2013*

**Math..**

4 ( x + 1 / 2 ) - 2 ( x + 3 / 2 ) <= 5 4 x + 4 / 2 - 2 x - 6 / 2 <= 5 4 x + 2 - 2 x - 3 <= 5 2 x - 1 <= 5 A dd 1 to both sides 2 x - 1 + 1 <= 5 + 1 2 x < = 6 Divide botg sides by 3 x <=3 x less or equal 3
*March 17, 2013*

**Mathematic**

In google type : wolframapha widget "Step-by-step integration" When yoe see list of results click on : WolfrAlpha Widget "Step-by-step integration" When page be open in rectangle type : cos^2(3x)sin^4(3x) (type exactly like that) and click option : Submit ...
*March 17, 2013*

**math**

1 - 3 / 4 = 4 / 4 - 3 / 4 = 1 / 4 2 / ( 1 / 4 ) = ( 2 / 1 ) / ( 1 / 4 = ( 2 * 4 ) / ( 1 * 1 ) = 8 / 1 = 8 $
*March 17, 2013*

**Math-**

When you multiply or divide left and right sides of inequality WITH NEGATIVE NUMBER , you MUST CHANGE the direction of the inequality
*March 17, 2013*

**Math-**

x / 2 - ( 3 x - 1 ) / 3 = [ 3 x - 2 ( 3 x - 1 ) ] / 6 = ( 3 x - 6 x + 2 ) / 6 = ( - 3 x + 2 ) / 6 x / 2 - ( 3 x - 1 ) / 3 < 1 / 4 ( - 3 x + 2 ) / 6 < 1 / 4 Multiply both sides by 6 - 3 x + 2 < 6 / 4 Multiply both sides by 4 - 12 x + 8 < 6 Subtract 8 to both sides...
*March 17, 2013*

**Algebra**

P = Perimeter L = Legth W = Width P = 2 L + 2 W = 2 ( L + W ) 38 = 2 ( L + 4 ) Divide both sides by 2 19 = L + 4 Subtract 4 to both sides 19 - 4 = L + 4 - 4 15 = L L = 15 in
*March 16, 2013*

**Pre-Calculus**

3 ^ ( - 3 ) = 1 / 27 OR 1 / 3 ^ 3 = 1 / 27
*March 15, 2013*

**fractions**

13 1 / 4 = 13 5 / 20
*March 14, 2013*

**fractions**

13 1 / 4 = 13 4 / 20 12 9 / 10 = 12 18 / 20 13 4 / 20 + 12 18 / 20 = 25 22 / 20 = 25 11 / 10 = 25 +10 / 10 + 1 / 10 = 25 + 1 + 1 / 10 = 26 1 / 10
*March 14, 2013*

**Algebra**

A is correct answer
*March 13, 2013*

**Math question**

If 1-(3x/2) <. 4 mean : 1 - ( 3 x / 2 ) < 0.4 then Subtract 1 to both sides 1 - ( 3 x / 2 ) - 1 < 0.4 - 1 - 3 x / 2 < - 0.6 Multiply both sides by 2 - 3 x < - 1.2 Divide both sides by - 3 ________________________________________ Remark: When you multiply or ...
*March 13, 2013*

**algebra**

2 x + ( 1 / 2 ) y = 24 Multiply both sides by 10 20 x + ( 1 / 2 ) y * 10 = 24 * 10 20 x + 5 y = 240 ________________________________________ 3 x + 5 y = 10 - 20 x + 5 y = 240 ________________________________________ 3 x - 20 x + 5 y - 5 y = 10 - 240 - 17 x = - 230 Divide both ...
*March 10, 2013*

**math**

a = smaller number b = larger number a = b - 18 a + b = 58 b - 18 + b = 58 2 b - 18 = 58 Add 18 to both sides 2 b - 18 + 18 = 58 + 18 2 b = 76 Divide both sides by 2 2 b / 2 = 76 / 2 b = 38 a = b - 18 a = 38 - 18 = 20 smaller number = 20 larger number = 38
*March 8, 2013*

**algebra I**

In google type: quadratic equation online When you see list of results click on: Free Online Quadratic Equation Solver:Solve by Quadratic Formula When page be open in rectangle type: 16x^2+56x-120=0 and click option: solve it You will see solution step-by step
*March 6, 2013*

**math**

42 % = 42 / 100 40 = x * 42 / 100 Multiply both sides by 100 40 * 100 = 42 x 4000 = 42 x Divide both sides by 42 4000 / 42 = x x = 95.238 OR 42 % = 42 / 100 = 0.42 x = 40 / 0.42 = 95.238
*March 6, 2013*

**maths**

The n - th term of a geometric progression with initial value a and common ratio r is given by: an = a * r ^ ( n - 1 ) In this case : a3 = a * r ^ ( 3 - 1 ) = a * r ^ 2 = 36 a8 = a * r ^ ( 8 - 1 ) = a * r ^ 7 = 8748 So you must solve two equations : a * r ^ 2 = 36 and a * r ^ ...
*March 6, 2013*

**Math (2nd Try)**

OR P = 6 x y ( 2x ^ 2 y + 1 ) + 2
*March 1, 2013*

**Math (2nd Try)**

OR P = 2 ( 6 x ^ 3 y ^ 2 + 3 x y + 1 ) P = 12 x ^ 3 y ^ 2 + 6 x y + 2 P = x y ( 12 x ^ 2 y + 6 ) + 2
*March 1, 2013*

**Math (2nd Try)**

P = 2 l + 2 w P = 2 ( l + w ) P = 2 ( 6 x ^ 3 y ^ 2 - 1 + 3 x y + 2 ) P = 2 ( 6 x ^ 3 y ^ 2 + 3 x y + 1 )
*March 1, 2013*

**MATH**

0.9 h = 0.9 * 60 min = 54 min
*February 26, 2013*

**MATH**

1 h = 60 min 0.9 h = 54 min 1.9 h = 1 h 54 min 1 h = 60 min write 5 h 05 min like : 5 h 05 min = 4 h + 60 min + 5 min = 4 h 65 min 5 h 05 min - 1.9 h = 4 h 65 min - 1 h 54 min = 3 h 11 min PM
*February 26, 2013*

**Algebra**

J = 45 Jims age C = Carols age Jim is 10 years older than 5 times his niece Carol J = 45 = 5 C + 10 45 = 5 C + 10 Subtract 10 to both sides 45 - 10 = 5 C + 10 - 10 35 = 5 C Divide both sides by 5 35 / 5 = 5 C / 5 7 = C Carol is 7 yo
*February 26, 2013*

**Math**

1. x ^ 2 + 4.5 x = 0 x ^ 2 + 9 x / 2 = 0 x / 2 ( 2 x + 9 ) = 0 Multiply both sides by 2 x ( 2 x + 9 ) = 0 First solution: obviously x = 0 Second solution: 2 x + 9 = 0 Subtract 9 to both sides 2 x + 9 - 9 = 0 - 9 2 x = - 9 Divide both sides by 2 x = - 9 / 2 Solutions are x = 0 ...
*February 23, 2013*

**math**

y-intercept is a point where the graph of a function or relation intersects with the y-axis of the coordinate system. OR y-intercept is a point where x = 0 1 / 2 y = 9 x + 5 Multiply both sides by 2 y = 18 x + 10 for x = 0 y = 18 * 0 + 10 = 0 + 10 = 10 y-intercept = 10 3 x = 6...
*February 22, 2013*

**alegbra**

In google type: How many rational numbers are there between 0 and 1 Yo will find answer.
*February 21, 2013*

**Algebra**

A parabola which opens up has a lowest point and a parabola which opens down has a highest point. The highest or lowest point on a parabola is called the vertex. The parabola is symmetric about a vertical line through its vertex, called the axis of symmetry. x - coordinate of ...
*February 21, 2013*

**Algebra**

x = - b / 2 a x = - 6 / [ 2 * ( - 1 ) ] x = - 6 / - 2 = 3 y = - 3 ^ 2 + 6 * 3 - 11 y = - 9 + 18 - 11 = - 2 Answer A
*February 21, 2013*

**Calculus**

d ( x ^ n ) / dx = n x ^ ( n - 1 ) d ( x ^ - 6 ) / dx = - 6 x ^ ( - 6 - 1 ) = - 6 x ^ - 7 d [ sqr 5 ( x ^ - 6 ) ] / dx = sqr 5 ( - 6 ) x ^ - 7 = - 6 sqr 5 / x ^ 7
*February 21, 2013*

**Math**

1 + n / 16 = 2 Subtract 1 to both sides 1 + n / 16 - 1 = 2 - 1 n / 16 = 1 Multiply both sides by 16 n * 16 / 16 = 1 * 16 n = 16 Proof: 1 + n / 16 = 2 1 + 16 / 16 = 2 1 + 1 = 2
*February 18, 2013*

**Math (PreAlgebra) 8thG**

V = ( 4 / 3 ) * pi * r ^ 3 V = ( 4 * pi * r ^ 3 ) / 3 V = 4 * 3.1416 * 10 ^ 3 / 3 V = 4 * 3.1416 * 1000 / 3 V = 12566.4 / 3 V = 4188.8 ft ^ 3 Round to the nearest whole number V = 4189 ft ^ 3
*February 18, 2013*

**College Algebra**

In google type this question and you will see answer
*February 16, 2013*

**Algebra**

Remark: 12 = 4 * 3 9 = 3 * 3 12 / 9 = 4 * 3 / ( 3 * 3 ) = 4 / 3 ________________________________________ C = number of cats D = numbers of dog C = D + 4 C / D = 12 / 9 C / D = 3 * 4 / ( 3 * 3 ) C / D = 4 / 3 ________________________________________ In a pet store there are 4 ...
*February 13, 2013*

**maths**

C = Cost n = nubers of friends If they all contributed $24, then they would be $6 short of the total: n * 24 = C - 6 Add 6 to both sides 24 n + 6 = C - 6 + 6 24 n + 6 = C C = 24 n + 6 If they all contributed $25, then they would have $3 more than needed. n * 25 = C + 3 25 n = ...
*February 13, 2013*

**maths**

2 / x − 24 / y = − 1 Divide both sides by 2 1 / x - 12 / y = - 1 / 2 Add 12 / y to both sides 1 / x - 12 / y + 12 / y = - 1 / 2 + 12 / y 1 / x = 12 / y - 1 / 2 6 / x + 33 / y = 2 6 * ( 12 / y - 1 / 2 ) + 33 / y = 2 72 / y - 6 * 1 / 2 + 33 / y = 2 72 / y - 3 + 33 / ...
*February 13, 2013*

**maths**

140 / 35 = 4 h
*February 13, 2013*

**MATH**

C = Circumference d = diameter C = d pi Divide both sides by pi C / pi = d d = 50 / 3.1416 = 15.915457 m d = 15.9 m rounded to the nearest tenth
*February 9, 2013*

**math**

72 x 5 / 8 = 72 x 5 / 8 = 360 / 8 = 45
*February 6, 2013*

**Math**

( 6 / 10 ) * 10 = 6
*February 6, 2013*

**math**

OR 1 / 3 of 33 = 11 2 / 3 of 33 = 2 * 11 = 22
*February 5, 2013*

**math**

( 2 / 3 ) * 33 = 66 / 3 = 22
*February 5, 2013*

**math**

2 x + y = 6 Subtract 2 x to both sides 2 x + y - 2 x = 6 - 2x y = 6 - 2x 3 x + 4 y = 4 3 x + 4 ( 6 - 2 x ) = 4 3 x + 24 - 8 x = 4 - 5 x + 24 = 4 Subtract 24 to both sides - 5 x + 24 - 24 = 4 - 24 - 5 x = - 20 Divide both sides by - 5 - 5 x / - 5 = - 20 / - 5 x = 4 y = 6 - 2x y...
*February 5, 2013*

**College Algebra--Still Confused**

In google type: quadratic equation online When you see list of result click on: Free Online Quadratic Equation Solver:Solve by Quadratic Formula When page be open in rectangle type your equation and cilck option: solve it! You will see solutions step-by step and discriminant ...
*February 5, 2013*

**5th grade math**

4 / ( 1 / 3 ) = 4 * 3 = 12 OR 1 / 3 yard to make 1 bow 1 yard to make 3 bow 4 * 3 = 12
*February 4, 2013*

**math**

80 % = 80 / 100 = 4 * 2 * 10 / ( 10 * 2 * 5 ) = 4 / 5
*February 4, 2013*

**algebra**

x ^ 2 - x - 20 =( x + 4 ) ( x + 5 ) ( x - 5 ) / ( x ^ 2 - x - 20 )= ( x - 5 ) / [ ( x + 4 ) ( x + 5 ) ] = 1 / ( x + 4 ) Your answer is correct
*February 3, 2013*

**math**

1 yd = 3 ft 1 ft = 1/3 yd 7 3/5 = 7 + 3/5 = 35/5 + 3/5 = 38 / 5 7 3/5 ft =( 38/5 ) * 1/3 = 38/15 yd = 2.5333333333 yd
*January 27, 2013*

**math - grade 7**

d = 2 r d = 2 * 4.26 = 8.52 m A = d ^ 2 pi / 4 A = 8 ^ 2 pi / 4 A = 64 pi / 4 A = 16 pi mm ^ 2 A = 16 * 3.14 = 50.24 mm ^ 2
*January 24, 2013*

**college algebra**

( 9.87x 10 ^ 6 ) (34 x 10 ^ 11 ) = 9.87 x 34 x 10 ^ 6 x 10 ^ 11 = 335.58 x 10 ^ ( 6 + 11 ) = 335.58 x 10 ^ 17 = 3.3558 x 10 ^ 2 x 10 ^ 17 = 3.3558 x 10 ^ ( 2 + 17 ) = 3.3558 x 10 ^ 19 Your answer is correct.
*January 23, 2013*

**pre- algebra**

D. f( x ) = 4 - x for x = 1 f ( x ) = 4 - 1 = 3 for x = 2 f ( x ) = 4 - 2 = 2 for x = 3 f ( x ) = 4 - 3 = 1 for x = 4 f ( x ) = 4 - 4 = 0
*January 22, 2013*

**MATH**

In google type: unit converter barel gallon you will find many sites
*January 22, 2013*

**Math**

4. C 3. B
*January 22, 2013*

**Math**

3 a + 6 b + 9 c = 3 ( a + 2 b + 3 c ) = 3 * 34 = 102
*January 18, 2013*

**math**

4 x + 6 y = 1 / 8 - 3 x + 7 y = 1 / 10 _________________________ x - y = 1 / 8 - 1 / 10 x - y = 5 / 40 - 4 / 40 x - y = 1 / 40 Add y to both sides x - y + y = 1 / 40 + y x = y + 1 / 40 4 x + 6 y = 1 / 8 4 ( y + 1 / 40 ) + 6 y = 1 /8 4 y + 4 / 40 + 6 y = 1 / 8 10 y + 1 / 10 = 1...
*January 17, 2013*

**Math 6**

5 1 / 2 = 5 + 1 / 2 = 10 / 2 + 1 / 2 = 11 / 2 8 * 5 1 / 2 = 8 * 11 / 2 = 88 / 2 = 44 OR 5 1 / 2 = 5.5 8 * 5.5 = 44
*January 17, 2013*

**marh 150 help**

2 x ^ 7 - 9 x ^ 7 = - 7 x ^ 7 100 % - 30 % = 70 % = 70 / 100 = 0.7 80 * 0.7 = 56 $
*January 16, 2013*

**math**

y = ( 1 / 3 ) x + 2 4 x + 9 y = 24 4 x + 9 [ ( 1 / 3 ) x + 2 ] = 24 4 x + ( 9 / 3 ) x + 18 = 24 4 x + 3 x + 18 = 24 7 x + 18 = 24 Subtract 18 to both sides 7 x - 18 = 24 - 18 7 x = 6 Divide both sides by 7 x = 6 / 7 y = ( 1 / 3 ) x + 2 y = ( 1 / 3 ) 6 / 7 + 2 y = 1 * 6 / ( 3...
*January 15, 2013*

**Math**

2 y + 4 x = 3 ( y - x ) + 8 2 y + 4 x = 3 y - 3 x + 8 Subtract 4 x to both sides 2 y + 4 x - 4 x = 3 y - 3 x + 8 - 4 x 2 y = 3 y - 7 x + 8 Subtract 3 y to both sides 2 y - 3 y = 3 y - 7 x + 8 - 3 y - y = - 7 x + 8 Multiply both sides by - 1 y = 7 x - 8 A straight line on the ...
*January 15, 2013*

**math**

Side of square : a = sqrt ( 49 ) = 7 cm Side of new square : a1 = 7 * 5 / 8 = 35 / 8 = 4.375 cm Area of new square : A1 = ( 35 / 8 ) ^ 2 = 1225 / 64 = 4.375 ^ 2 = 19,140625 cm ^ 2
*January 14, 2013*

**math**

cos ^ 2 ( x ) - sin ^ 2 ( x ) = cos ( 2x ) 2 sin ( x ) cos ( x ) = sin ( 2 x ) Equation : cos ^ 2 ( x ) - 2 sin( x ) cos( x ) - sin ^ 2 ( x ) = 0 we can write like : cos ( 2 x ) - sin ( 2 x ) = 0 Add sin ( 2 x ) to both sides cos ( 2 x ) - sin ( 2 x ) + sin ( 2 x ) = 0 + sin...
*January 12, 2013*

**Math**

7 x + 5 = 4 x + 5 + 3 x ________________________________________ 7 x + 5 = 4 x + 5 + 3 x 7 x + 5 = 7 x + 5 That ic correct for all value of x ( infinite number of solutions ) ________________________________________
*January 12, 2013*

**algebra**

9 x + 8 = 2 + 8 9 x + 8 = 10 Subtract 8 to both sides 9 x + 8 - 8 = 10 - 8 9 x = 2 Divide both sides by 9 x = 2 / 9
*January 11, 2013*

**Math -3**

6 / 5 = ( 5 + 1 ) / 5 = 5 / 5 + 1 / 5 = 1 + 1 / 5 = 1 1 / 5 = 1 .2 13 / 5 = ( 10 + 3 ) / 5 = 10 / 5 + 3 / 5 = 2 + 3 / 5 = 2 3 / 5 = 2.6 9 / 5 = ( 5 + 4 ) / 5 = 5 / 5 + 4 / 5 = 1 4 / 5 = 1.8 7 / 5 = ( 5 + 2 ) / 5 = 1 + 2 / 5 = 1 2 / 5 = 1.4
*January 10, 2013*

**Math**

1 in = 2.54 cm 1 cm = 1 in / 2.54 d ( in ) = 2.4 / 2.54 None of these
*January 10, 2013*

**Algebra 2**

2 x ^ 2 = 5 x + 12 Subtract 5 x + 12 to both sides 2 x ^ 2 - ( 5 x + 12 ) = 5 x + 12 - ( 5 x + 12 ) 2 x ^ 2 - 5 x - 12 = 0 Divide both sides by leading coefficient ( 2 ) x ^ 2 - 5 x / 2 - 6 = 0 Add 6 to both sides x ^ 2 - 5 x / 2 - 6 + 6 = 0 + 6 x ^ 2 - 5 x / 2 = 6 ...
*January 10, 2013*

**calculus**

ln(5x)
*January 7, 2013*

**math**

5 n = 32 Divide both sides by 5 n = 32 / 5 n = 6.4
*January 7, 2013*

**math**

a b - ( a - b ) = 0.5 * 0.4 - ( 0.5 - 0.4 ) = 0.2 - 0.1 = 0.1
*January 7, 2013*