Question

Shawna and her best friend Keisha go shopping.

The function p(x) = 3x^4 + 2x^3 − 4x^2 + 21 represents how much money each girl spent based on the number of hours they were shopping. If Shawna and Keisha each go shopping for 2 hours, how much money did they spend together?

$37
$69
$101
$138

Answer 1

138

Explanation:

p(x) = 3x^4 + 2x^3 − 4x^2 + 21

Let x = 2

p(2) = 3*(2)^4 + 2*(2)^3 − 4*(2)^2 + 21

= 3*16+2*8-4*4+21

=48+16-16+21

= 69

This is per girl

There are 2 girls

2 * 69

138