The numbers x and y are inversely proportional. When the sum of x and y is 42, x is twice y. What is the value of y when x = -8? PLEASE HELP

y= -4

Step-by-step explanation:

x+y=42.   We know that x plus y equals 42.

x=2y .   We also know that x equals twice y.

2y+y=42.   Since we know that x=2y, we're going to replace x with 2y from the original equation, simplified would be 3y=42.

y=14.   3y=42 simplified is y=14, this is because we divided both sides by 3 (since 3 and 42 are both divisible by 3) (btw divisible by 3 simply means that it can be divided by 3)

x+14=42.   Now that we know what y equals, let's replace y with 14 from the original equation.

x=28.  Now that we know that x=28 and y=14, we know that y is always x/2.

When x=-8, we divide it by 2 and get, -4.

Not absolutely positive as this was all mental math, but hope this helps! :)

step-by-step explanation:

equation

you are asked to write the equation

  expression = 0

using the given expression. when you do that, you have

  2x^2-2x-12 = 0

factoring

you can see that each of the coefficients is even, so a factor of 2 can be removed immediately.

  2(x^2 -x -6) = 0

if you multiply the binomials (x+a)(x+b), you get

  (x +a)(x +b) = x^2 +(a+b)x +ab

this tells you the coefficient of x is the sum of two factors of the constant term. here, that means -1 is the sum of two factors of -6. we want to know those factors so we can factor the trinomial.

  -6 = -1×6 = -2×3 = -3×2 = -6×1

the factor pair that sums to -1 is {-3, 2}, so our factorization is

  2(x -3)(x +2) = 0

solutions

the solutions to this equation are the values of x that make the product zero. a product is zero only when only of the factors of the product is zero. here, that means

  x - 3 = 0

  x = 3 . . . add 3 to both sides of the equation

or

  x +2 = 0

  x = -2 . . . add -2 to both sides of the equation

the solutions to the equation are x=3 or x=-2. both of these values of x satisfy the equation—they make it be true.

1e+27

step-by-step explanation: