Question

Which statement about the quadratic function m(x) = -x2 + 11x - 28 is true?

A. Since m(x) =-(x - 4)(x + 7), the zeros for m(x) are 4 and -7.
B. Since m(x) = -(x - 4)(x - 7), the zeros for m(x) are 4 and 7.
C. Since m(x) = -(x + 4)(x + 7), the zeros for m(x) are -4 and -7.
D.Since m(x) = -(x + 4)(x-7), the zeros for m(x) are -4 and 7.

Answer 1

Explanation:

So first you want to take the constants of -x^2 (which would be -1) and -28 and multiply them to get the product of 28.

Since the other constant of 11x is 11, you want to find 2 numbers whose sum give you 11 and whose product give you 28. That would be 4 and 7, because 4 + 7 = 11 and 4 * 7 = 28. But since you have -x^2 you will want to put a negative sign in front of one of your x variables and in front of 4 or 7, so that you still get 11x when you factor it out.

So you would set up the equation like this (-x+4)(x-7) = 0. To make it easier to find the values of x, you could just write it out as -x+4 = 0 and x-7 = 0. Than you solve for x in botn euqations.

Then you would find out that x = 4, 7.

Does this help?

Answer 2

D.Since m(x) = -(x + 4)(x-7), the zeros for m(x) are -4 and 7.

Explanation: