Question

Three friends, Nakobe, Mikah, and Ashton, are saving up money to buy microphones for their podcast. The total cost of the microphones is represented by the expression 8x2 − 4x + 9.

The friends have already saved the following amounts:

Nakobe: x2
Mikah: x − 14
Ashton: 2x + 6

Which expression represents the amount of money the friends still need to buy the microphones?

x2 + 3x − 8
x2 + 3x + 26
4x2 + 4x + 9
7x2 − 7x + 17

Answer 1

7x^2 - 7x + 17

Explanation:

we can subtract what they already have from what they total cost for the microphones:

8x^2 - 4x + 9 - (x^2) - (x - 14) - (2x + 6)

simplify this:

8^2 - 4x + 9 - x^2 - x + 14 - 2x - 6 =

7x^2 - 7x + 17