Which is the value of this expression when x=-2

A) x^2 +x -30 = 0 is factored by looking for two factors of 30 that differ by 1. We know ...  30 = 1*30 = 2*15 = 3*10 = 5*6The last two factors differ by 1, so we can factor the trinomial as  (x +6)(x -5) = 0
b) The solutions are found by finding values of x that make these factors zero. The only way the product will be zero is if one or more of the factors is zero.  x + 6 = 0  x = -6 . . . . . subtract 6
  x - 5 = 0  x = 5 . . . . . add 5
The solutions are x = -6 or x = 5These are the values of x that will satisfy the equation (make it true). What they mean depends on the meaning of the variable and the situation the equation is a model of.

What is the longest side?

square root of 1700

What is the square of the longest side?

1700

What is the sum of the squares of the two shorter sides?

1700

Does the window frame form right triangles?

Yes, the sum of the square of the two shorter sides equals the square of the longest side.