The variable expression is x(shirt cost) + 8. The answer is x+8.

For each boy, there are 5 girls
Independent: number of hours
Dependent: Earned income
Domain: Between and including, 0 and 40 hours
Range: Between and including, 0 and 480$
(f+g)(x)=f(x)+g(x)=3x+1+x²-6=x²+3x-5
answer is D
4+5=9 divided by 3 is 3 times 4 is 12. so it's 12
hope this helps;)