Thursday

February 11, 2016
Total # Posts: 1,926

**Math**

...limit as x approaches what value?
*January 30, 2012*

**MATH**

note that when we substitute 59 to the expression in numerator and denominator, (sqrt(x+5)-8)/(x-59) (sqrt(59+5)-8)/(59-59) (sqrt(64)-8)/0 8-8/0 0/0 thus we use L'hopital's Rule: we separately get the derivative of numerator and denominator. thus, (num) = (sqrt(x+5)-8...
*January 30, 2012*

**chemistry**

the only chemical change there is the burning of wood.
*January 29, 2012*

**chemistry**

Burning of gasoline (combustion) note that phase changes are physical changes only. hope this helps~ :)
*January 29, 2012*

**Precalculus**

yes.
*January 29, 2012*

**Precalculus**

ahh i think you mean cube root for that ^3sqrt(64). if so, log(base4) of (cuberoot(64)) note that we can rewrite cuberoot(64) as cuberoot(4^3) which is equal 4. log(base4) of 4 = 1 hope this helps~ :)
*January 29, 2012*

**Algebra II**

#1 (2x^(-3)y^(2))^(-2) (2)^(-2) * x^(-3*(-2)) * y^(2*(-2)) (1/4) * x^(6) * (1/y^4) (x^6)/(4y^4) #2 (z^4)/(2z^3) z/2 hope this helps~ :)
*January 29, 2012*

**algebra**

recall that the slope, m, is given by the equation, m = (y2 - y1)/(x2 - x1) where (x1, y1) = coordinates of first point (x2, y2) = coordinates of second point substituting, m = (1 - 6)/(-3 - 5) m = (-5)/(-8) m = 5/8 hope this helps~ :)
*January 29, 2012*

**algebra**

4x - 15/2 = 1/2 first we transpose all terms with no variable x to the right side of equation. that is, we transpose - 15/2 to the right. note that when we transpose, we change the sign to its opposite. thus is becomes positive: 4x = 1/2 + 15/2 when adding fractions, we first ...
*January 29, 2012*

**Precalculus**

Bosnian's answer is correct. I'll just show how to get 0. 6^(x+3) - 6^x = 215 recall that when multiplying exponents of the same base, we add their exponents. for example, x^2 * x^4 = x^(2+4) = x^6 now we do the opposite to 6^(x+3). we'll separate this into, 6(x+3...
*January 29, 2012*

**math**

SA of sphere = 4*pi*r^2 154 = 4*3.14*r^2 r = 3.502 V of sphere = (4/3)*pi*r^3 V = (4/3)*3.14*(3.502)^3 V = 170.81 cm^3 hope this helps~ :)
*January 29, 2012*

**Precalculus**

5^(2-x) = 1/125 note that we can rewrite 125 as 5^3 thus, we replace the term on the right side of equation: 5^(2-x) = 1/(5^3) note also that we can still rewrite 1/(5^3) as 5^(-3). thus, 5^(2-x) = 5^(-3) now that the bases (the 5) are equal, we equate their exponents: 2 - x...
*January 28, 2012*

**math**

..i think you forgot to type the expressions..
*January 28, 2012*

**algebra**

-3|6n-2| +5 = 8 case I: absolute value is positive. thus, -3(6n-2) + 5 = 8 -3(6n-2) = 8 - 5 -3(6n-2) = 3 6n - 2 = -1 6n = 1 n = 1/6 case II: absolute value is negative. thus, -3[-(6n-2)] + 5 = 8 3(6n-2) + 5 = 8 3(6n-2) = 3 6n - 2 = 1 6n = 3 n = 1/2 NOTE: these are not yet the ...
*January 28, 2012*

**trig**

oops i forgot the +/- sign: cos (theta) = +/- sqrt(3) / 2 theta = +/- arccos [ sqrt(3) / 2 ] theta = π/6 , 11π/6 , 5π/6 , 7π/6
*January 22, 2012*

**trig**

4cos^2 theta = 3 cos^2 theta = 3/4 cos (theta) = sqrt(3) / 2 theta = arccos [ sqrt(3) / 2 ] theta = π/6 , 11π/6 hope this helps~ XD
*January 22, 2012*

**math problem**

we start performing the operation inside the parenthesis, then going outside of the parenthesis: 8[-73-(-61-28)] 8[-73-(-89)] 8[-73+89] 8[16] 128 hope this helps~ XD
*January 22, 2012*

**math**

5x^2 = 9x + 2 first we transpose all terms to the left side of the equation: 5x^2 - 9x - 2 = 0 then we factor (since it's factorable): (5x + 1)(x - 2) = 0 5x + 1 = 0 5x = -1 x = -1/5 x - 2 = 0 x = 2 therefore, x = -1/5 and x = 2 hope this helps~ XD
*January 22, 2012*

**physics**

what is the distance, given the velocity that has magnitude 1.2 m/s within 40 min.?
*December 29, 2011*

**math **

(a) miles per hour 26.2 / 2.5 = ? (b) miles per minute: first convert 2.5 hours to minutes. 2.5 * 60 = 150 min 26.2 / 150 = ? (c) minutes per mile: just get the reciprocal of your answer in (b)
*November 10, 2011*

**Math**

when you want a variable to be squared you use this symbol, ^ , which means "raised to". in the problem, s = ut + (1/2)*(g*t^2) s - (1/2)*(g*t^2) = ut [ s - (1/2)*(g*t^2) ]/t = u, or u = [ s - (1/2)*(g*t^2) ]/t
*November 10, 2011*

**math**

(a) to write this in standard form, you use completing the square for both variables x and y. x^2 + y^2 + 8y - 65 = 0 x^2 + (y^2 + 8y + 16) - 65 - 16 = 0 x^2 + (y + 4)^2 - 81 = 0 x^2 + (y + 4)^2 = 81 x^2 + (y + 4)^2 = 9^2 (b) Center: C(0, -4) Radius = 9 to get intercepts, x-...
*November 10, 2011*

**Algebra**

#1. (5y-3)/3 - (2y-1)/2=1 [(5y-3)/3 - (2y-1)/2 = 1]*6 2(5y-3) - 3(2y-1) = 6 10y - 6 - 6y + 3 = 6 4y - 3 = 6 4y = 9 y = 9/4 #2. -5(-2(x-1) - (x+1)) = 9 -5(-2x + 2 - x - 1) = 9 -5(-3x + 1) = 9 15x - 5 = 9 15x = 14 x = 14/15 #3. .08n-.09(n-2)=5-.08 0.08n - 0.09n + 0.18 = 4.92 -0....
*November 1, 2011*

**math**

let x = larger number let y = smaller number then we set up the equations. since their difference is 25, x - y = 25 : equation (1) since the smaller is 1/6 of the larger, y = (1/6)x : equation (2) we substitute equation (2) to equation (1): x - (1/6)x = 25 (5/6)x = 25 x = 25*6...
*November 1, 2011*

**algebra**

to get the x-intercept, we set y = 0 and solve for x: 2x + 3y = 15 2x + 3(0) = 15 2x = 15 x = 7.5 thus, x-intercept is at (7.5, 0) to get y-intercept, we set x = 0 and solve for y: 2x + 3y = 15 2(0) + 3y = 15 3y = 15 y = 5 thus, y-intercept is at (0, 5) to plot this, locate ...
*November 1, 2011*

**algebra**

to get the x-intercept, we set y = 0 and solve for x: 2x + 3y = 15 2x + 3(0) = 15 2x = 15 x = 7.5 thus, x-intercept is at (7.5, 0) to get y-intercept, we set x = 0 and solve for y: 2x + 3y = 15 2(0) + 3y = 15 3y = 15 y = 5 thus, y-intercept is at (0, 5) to plot this, locate ...
*November 1, 2011*

**algebra**

to get the y-coordinates, we just substitute the value of the x-coordinates given. at x = -2: y = 4x + 2 y = 4(-2) + 2 y = -8 + 2 y = -6 thus (-2, -6) at x = 1: y = 4x + 2 y = 4(1) + 2 y = 4 + 2 y = 6 thus (1, 6) at x = -3: y = 4x + 2 y = 4(-3) + 2 y = -12 + 2 y = -10 thus (-3...
*November 1, 2011*

**algebra**

v = (1/3)t + 12 to plot this, the easiest way (for me) is to get the x- and y-intercept (in this case, the x-axis = t-axis, and y-axis = v-axis). to get t-intercept, we let v = 0 and solve for t: v = (1/3)t + 12 0 = (1/3)t + 12 -(1/3)t = 12 t = -36 thus t-intercept is at (-36...
*November 1, 2011*

**chemistry**

cations - ions with positive charges (ex: Na+ , Ca2+) anions - ions with negative charges (ex: Cl- , OH-)
*October 29, 2011*

**chemistry**

Molarity = moles of solute / Liters of solution moles = mass given / molar mass substituting, Molarity = (5.20/36.46)/3 Molarity = 0.0475 M hope this helps~ :)
*October 29, 2011*

**math**

let x = hypotenuse let y = the length of the other leg we have two equations, two unknowns here. recall that perimeter of a triangle is just, P = a + b + c substituting, 38.7 = x + y + 12.5 x + y = 38.7 - 12.5 x + y = 26.2 x = 26.2 - y : : equation (1) recall that for any ...
*October 29, 2011*

**Algebra 1**

we are solving for x. To get x alone, we need to isolate the term with x only to one side of the equation. In this case, let's isolate the term with x (which is 0.3x) on the right side, thus we will transpose the -9.1 on the left side. To do this, the its sign must be ...
*October 29, 2011*

**math**

the surface area of a rectangular solid is given by SA = 2(LW + LH + WH) where W = width, L = length, H = height if we double all the dimensions, SA' = 2[(2L)(2W) + (2L)(2H) + (2W)(2H)] SA' = 2[4LW + 4LH + 4WH] SA' = 2*4[LW + LH + WH] SA' = 4*SA therefore, what...
*October 28, 2011*

**algebra**

15/30 * 100 = 50%
*October 28, 2011*

**algebra**

let x = number note that 80% is also equal to 0.8 88 = (0.8)x x = 88/0.8 x = 110
*October 28, 2011*

**Algebra**

we just substitute the value of x and y to the equation: 3x + c = 5y 3(-4) + c = 5(0) -12 + c = 0 c = 12
*October 28, 2011*

**algebra**

-9 - (-3) -9 + 3 -6
*October 28, 2011*

**Algebra**

let x = number of multiple questions she got right. then we set up the equation and solve for x: (4-1)*7 + 3x = 78 21 + 3x = 78 3x = 57 x = 19 hope this helps~ :)
*October 28, 2011*

**Geometry**

it's difficult to explain it here because you need to draw to see it clearly. i'll provide a link to for you to see the drawing (though it's little unclear :P) first you draw the circle and the parallel chords. connect the center of circle to one of the endpoints ...
*October 28, 2011*

**science**

recall that heat absorbed released is given by Q = mc*(T2 - T1) where m = mass (in g) c = specific heat capacity (in J/g-k) T = temperature (in C or K) *note: Q is (+) when heat is absorbed and (-) when heat is released. we're looking for (T2 - T1) here. substituting, ...
*October 28, 2011*

**science**

recall that heat absorbed released is given by Q = mc*(T2 - T1) where m = mass (in g) c = specific heat capacity (in J/g-k) T = temperature (in C or K) *note: Q is (+) when heat is absorbed and (-) when heat is released. substituting, Q = (480)*(0.97)*(234 - 22) Q = 98707 J = ...
*October 28, 2011*

**trignometry**

the derivative of cot x = -csc^2 x the derivative of tan x = sec^2 x .. and you do this: [ low*d(high) - high*d(low) ] / (low)^2 where high = numerator low = denominator d(high) and d(low) = respective derivatives
*October 28, 2011*

**Math**

add the two equations to get y alone: y = -3/4x + 1/4 y = 3/4x - 3/4 -------------------------- 2y = -2/4 y = -1/4 then substitute this value of y to either of the equations and solve for x. in this case let's substitute this to the first give equation: y = -3/4x + 1/4 -1/...
*October 28, 2011*

**derivatives**

[ low*d(high) - high*d(low) ] / (low)^2 where high = numerator low = denominator d(high) and d(low) = respective derivatives first recall that the derivative of csc x = -(cot x)(csc x) therefore, [ x*(-6 (cot x)(csc x)) - 6 (csc x) ]/x^2 or -(6 csc x)*(x(cot x) + 1)/x^2 hope ...
*October 28, 2011*

**math **

but we don't se the diagram..
*October 28, 2011*

**HELP**

(3v - 9)/(3 - v) [3(v-3)]/[-1(v-3)] -3
*October 28, 2011*

**HELP**

it must be 4a^7t^2/3 (remove the t^2 from the denominator)
*October 27, 2011*

**chemistry**

to get this, we just divide the final volume by the initial volume: 55.5 / 7.4 = ?
*October 27, 2011*

**Algebra**

at x = 2 8y + 7*2 = -25 8y = -25 - 14 y = -39/8 at x = 4 8y + 7*4 = -25 8y = -25 - 28 y = -53/8 at x = 6 8y + 7*6 = -25 8y = -25 - 42 y = -67/8 thus it's (2, -39/8), (4, -53/8), (6, -67/8) hope this helps~ :)
*October 27, 2011*

**Precalc**

x^2 - 4x + 6 first, yo only focus on the first two terms: x^2 and -4x. let's put a parenthesis to enclose them: (x^2 - 4x) + 6 now, to complete the square, what we do is get the half of b (b is the numerical coefficient of x, and in this case, is -4) and we square it: (-4/...
*October 27, 2011*

**Algebra**

.25(250)+250/250 62.5 + 1 63.5
*October 27, 2011*

**Algebra**

yes.
*October 27, 2011*

**Alg. II**

54 + 16x^3 2(8x^3 + 27) then recall the how we factor sum of two cubes: a^3 + b^3 = (a+b)(a^2 - ab + b^2) therefore, 2(2x+3)(4x^2 - 6x + 9) hope this helps~ :)
*October 27, 2011*

**Trig/Algebra II**

(3+√2)/(3-√2) (3+√2)*(3+√2)/(3-√2)(3+√2) (9 + 6√2 + 2)/(9-2) (11 + 6√2) / 7 it's A.
*October 27, 2011*

**physics**

Q = Pt = mc(T2-T1) where Q = heat/energy (in J) P = Power (in W) t = time (in s) m = mass (in kg) c = specific heat capacity (in J/kg-K) = 4.184 J/kg-K for water T = temperature (in C or K) we're solving for mass. substituting, (7.5*1000)*(3*24*60*60) = m*4.184*(70-18) ...
*October 27, 2011*

**Int. Algebra**

A. substitute r = 1800 to the equation: 1800 = 200*sqrt(t+3) - 600 2400 = 200*sqrt(t+3) 12 = sqrt(t+3) 144 = t+3 t = 141 hours B. recall that area of circle is just A = pi*r^2. thus we square both sides and multiply by pi: r(t) = 200*sqrt(t+3) - 600 r^2 = 40000(t+3) - 240000*...
*October 26, 2011*

**math**

3x + 5y = 55 the condition that must be satisfied is that x, y and z must all be multiples of 5. first, we guess value of x (which must be a multiple of 5). And then we solve for corresponding value of y. Note that the value of y calculated must also be a multiply of 5. If it...
*October 26, 2011*

**algebra**

let x = cost of a record 20x + 0.89
*October 26, 2011*

**science**

the conversion factor for calories (cal) and joules (J) is: 1 cal = 4.184 J now to convert calories to joules, we multiply 4000 cal by 4.184 J / 1 cal so that the cal unit will be canceled, and the numerator will have the unit J: 4000 cal * 4.184 J / cal = 16736 J hope this ...
*October 26, 2011*

**math**

recall PEMDAS: Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction. this is the order which must be followed when performing multiple operations. therefore, (3 x 6) + 12/2 - 8 18 + 12/2 - 8 18 + 6 - 8 24 - 8 16 hope this helps~ :)
*October 26, 2011*

**math**

that's right. you subtract 13 to both sides of equation to get x alone. x + 13 - 13 = 25 - 13 x = 12
*October 26, 2011*

**Math**

recall that rate is just distance travelled over time, or v = d/t let x = time required for them to meet thus since they are paddling toward each other, we add their rates and multiply it by the time required and equate this distance to 33: (4 + 7)x = 33 11x = 33 x = 3 hours ...
*October 26, 2011*

**MATH 7th GRADE**

everything is correct except #7. it must be 8 1/4 = 33/4 1 3/8 = 11/8 (33/4) / (11/8) 33/4 * 8/11 = 6 hope this helps~ :)
*October 26, 2011*

**Calculus**

recall that to get the derivative of 2 functions of x which are multiplied, we do this: d/dx f(x)g(x) = f'(x)g(x) + f(x)g'(x) therefore, d/dx 3x((x+1)^1/2) = 3(x+1)^(1/2) + (3x)*(1/2)*(x+1)^(-1/2) hope this helps~ :)
*October 26, 2011*

**math**

let x = number of chicken let y = number of goat let 100 - (x+y) = number of sheep 0.5x + 3.5y + 5[100-(x+y)] = 100 0.5x + 3.5y + 500 - 5x - 5y = 100 -4.5x - 1.5y = -400 9x + 3y = 800 there are actually many possible answers here since you got only 1 equation and 2 unknowns. ...
*October 26, 2011*

**Math**

a, c, f
*October 25, 2011*

**Chemistry **

assuming ideal gas, we can use the formula for constant pressure: V1/T1 = V2/T2 where V = volume T = temperature (in Kelvin) note that to convert to Kelvin, K = C + 273 substituting, 39.5 / (25 + 273) = 7.7 / T2 now solve for T2. subtract 273 to convert it to deg C units
*October 25, 2011*

**Math**

we subtract the price of magazine from 59.99 to get the total amount of the 3 books: 59.99 - 1.99 = 58.00 (cost of 3 books) thus, we divide this by 3 to get the price of each book: 58.00 / 3 = 19.33 hope this helps~ :)
*October 24, 2011*

**math**

recall that speed is distance travelled over time. let x = speed of the other car. then we set-up the equation. when you draw the directions they're travelling, you will form a right triangle. thus recall that in a right triangle, the hypotenuse (in this the the distance ...
*October 24, 2011*

**math**

recall that speed is distance travelled over time. let x = speed of the other car. then we set-up the equation. when you draw the directions they're travelling, you will form a right triangle. thus recall that in a right triangle, the hypotenuse (in this the the distance ...
*October 24, 2011*

**geometry**

but we need to see the figure..
*October 24, 2011*

**math**

recall that speed is distance travelled over time, or v = d/t substituting, v = 10/30 v = 0.33 km/min hope this helps~ :)
*October 24, 2011*

**Trigonometry**

sec (π - x) = -sec (x) when we prove, we only manipulate the left side. first, recall that sec (x) = 1/cos x. thus we can replace the the term on the left side of equation by: 1 / cos (π - x) then recall the sum/difference identity for cosine: cos(A−B) = cos A ...
*October 23, 2011*

**Math **

to get this, we get the derivative of h(t) with respect to t, and equate it to zero: h(t) = 2 + 28t - 4.9t^2 0 = 28 - 9.8t 9.8t = 28 t = 2.86 s *note that the derivative of a function is the slope of the tangent line at the given point (in this problem, the point referred is ...
*October 23, 2011*

**Math**

first we represent the unknowns using variables: let x = length let y = width recall that perimeter of rectangle is just, P = 2x + 2y since P is given (which is 400), we can get an expression of width in terms of length: 400 = 2x + 2y 400 - 2x = 2y y = 200 - x then to get the ...
*October 23, 2011*

**Math **

first we solve for hypotenuse: to get the hypotenuse we use pythagorean theorem: c^2 = a^2 + b^2 where c = hypotenuse of the right triangle a and b = legs of right triangle substituting, c^2 = 6^2 + 3^2 c^2 = 36 + 9 c^2 = 45 c = 3*sqrt(5) therefore the perimieter is: P = a + b...
*October 23, 2011*

**Math**

C. because 5/25 = 1/5, while 4/24 = 1/6
*October 23, 2011*

**College Algebra**

y = (kx^3)/z substituting the given values to find the constant k, 16 = k(4^3)/8 16 = k(64)/8 16 = 8k k = 2 therefore, y = (2x^3)/z if x = 9 and z = 6, y = 2*(9^3)/6 y = 243 hope this helps~ :)
*October 23, 2011*

**calculus**

lim (5x^3 + 7x^2 - 9x + 14) as x = 7 to do this just substitute x = 7: 5*(7^3) + 7*(7^2) - 9*7 + 14 = 2009 hope this helps~ :)
*October 23, 2011*

**geomatry**

<d is always less than <e.
*October 23, 2011*

**chemistry**

assuming the gas is ideal, we can use the ideal gas law: PV = nRT where P = pressure (in atm) V = volume (in L) n = number of moles R = gas constant = 0.0821 L-atm/mol-K T = temperature (in K) note that n = mass given / molar mass. The molar mass of nitrogen (diatomic gas) is ...
*October 23, 2011*

**Algebra 2**

first represent the unknown using variable: let x = time required so that they will have the same number of rows. recall that rate = quantity/time, or quantity = rate*time in this problem, quantity refers to number of rows knitted. to set-up the equation, what we only know is ...
*October 23, 2011*

**maths**

you mean how did this happen: sqrt(245) = 7*sqrt(5) if so, first you factor out 245: 245 = 5 * 49 = 5 * 7 * 7 = 5 * 7^2 therefore, sqrt(5 * 7^2) we can also rewrite this as sqrt(5) * sqrt(7^2) we can take out the seven since the sqrt(7^2) is equal to 7, and leave the 5 inside...
*October 23, 2011*

**reposting maths qn as mistake in quantity**

i couldn't really think of a solution which is non-algebraic. but i just tried to simplify things in this solution: 16 Forks + 12 Spoons = 106.40 therefore, if we get the half of both the number of forks and spoons, the price will also be half: 8 Forks + 6 Spoons = 53.20 ...
*October 23, 2011*

**Math**

we'll work backwards: x = 3 and x = -2 x - 3 = 0 and x + 2 = 0 then we multiply both these functions of x: (x - 3)(x + 2) = 0 x^2 - 3x + 2x - 6 = 0 x^2 - x - 6 = 0 hope this helps~ :)
*October 23, 2011*

**Algebra**

2e^2 = 3h e^2 = (3/2)*h e = sqrt((3/2)*h)
*October 23, 2011*

**Pre Calculus**

f(x) = 1/sqrt(x+1) we can rewrite this as y = 1/sqrt(x+1) to get the inverse function, we replace x by y, and y by x, and solve for y: x = 1/sqrt(y+1) sqrt(y+1) = 1/x y + 1 = 1 / x^2 y = (1/(x^2)) - 1 f'(x) = (1/(x^2)) - 1 for #2, we do the same: f(x) = 1 - x^2 y = 1 - x^2...
*October 23, 2011*

**Physics**

i suggest you read "Twin Paradox"
*October 23, 2011*

**Science**

recall that heat absorbed or released is given by Q = mc(T2 - T1) where m = mass (in kg) c = specific heat capacity (in J/kg-K) T = temperature (in C or K) *note: Q is (+) when heat is absorbed, and (-) when heat is released. #1. we just substitute. the c for water is equal to...
*October 23, 2011*

**Math**

recall that the formula for discriminant: D = b^2 - 4ac if D < 0 : two imaginary roots D = 0 : one root D > 0 : two real roots thus, given the equation, we can substitute the values of a, b and c in the discriminant, which must be > 0: (2k - 3)^2 - 4(4)(1) > 0 4k^2...
*October 23, 2011*

**Adv algebra**

there is only one number which satisfies "the square of itself is equal to itself": it is 1. (0 is also the other but it is stated that q cannot be equal to 0) therefore, (x-1)(x-1) = x^2 + 2x + 1 p = 2 q = 1 hope this helps~ :)
*October 22, 2011*

**Maths Calculus**

we can rewrite this as sqrt(x^6)*sqrt(3x^5 + 1)*sin(7x) sqrt(3x^11 + x^6)*sin(7x) (3x^11 + x^6)^(1/2) * sin(7x) then recall that derivative of two functions of x that are multiplied is equal to, d/dx ( f(x)*g(x) ) = f'(x)g(x) + f(x)g'(x) therefore, (1/2)*(33x^10 + 6x^5...
*October 22, 2011*

**math**

let x = cost of bag let y = cost of shoes let 160 - (x+y) = cost of watch set up equations: (1) x = y + 15 (2) 160 - (x+y) = x - 20 solve simultaneously. we can either use elimination or substitution, but for this problem let's just use substitution. we substitute equation...
*October 22, 2011*

**science**

(a) recall that potential energy is stored energy, and is given by the formula: PE = mgh (units in Joules) where m = mass (in kg) g = acceleration due to gravity = 9.8 m/s^2 h = height (in m) if the reference position is at the floor (that is, h = 0), the PE is equal to PE = 4...
*October 22, 2011*

**Math **

we substitute the given values and solve for a. at x = 2, f(x) = 3: 3 = a(2^2) - 6(2) - 7 3 = 4a - 12 - 7 3 = 4a - 19 3 + 19 = 4a 22 = 4a a = 5.5 substituting back, f(x) = 5.5x^2 - 6x - 7 hope this helps~ :)
*October 21, 2011*

**Math**

let n = number (n/64) + 48
*October 21, 2011*

**MATH (REPLY FAST)**

4 - 3|m + 2| > -14 there are two cases here. Case I: |m + 2| = m + 2 4 - 3(m+2) > -14 4 - 3m - 6 > -14 -3m - 2 > -14 -3m > -12 m < 4 Case II: |m + 2| = -(m + 2) 4 - (-3(m+2)) > -14 4 + 3m + 6 > -14 3m + 10 > -14 3m > -24 m > -8 therefore, all ...
*October 21, 2011*

**chemistry**

one mole of solid Cobalt (II) Chloride reacts with 2 moles of Hydrogen Fluoride to yield one mole of solid Cobalt (II) Fluoride and two moles Hydrogen Chloride. *for #2 i think that's Pb not P6, and KCl, not KL. one mole of aqueous Lead (II) Nitrate reacts with two moles ...
*October 21, 2011*

**math**

let x = amount of money of Lexi let 250 - x = amount of amount of Marie then set up the equation: x - (2/5)x = 250 - x - 40 (3/5)x = 210 - x (3/5)x + x = 210 (8/5)x = 210 x = 210*(5/8) x = $ 131.25 (Lexi's money) 250 - x = 118.75 (Marie's money) hope this helps~ :)
*October 21, 2011*