Ican not find the answer to this problem 4x+8=7.2+5x

4x+8=7.2+5x

Subtract 4x from both sides:
8=7.2+x

Subtract 7.2 from both sides:
0.8=x

x=0.8

Part 1:
Variable x - number of the hours.
Variable y - her total income.
y = f ( x ), Her total income is a function of the hours she worked.
Part 2 :
The function is: y = 15 * x
Part 3 :
f ( 35 ) = 15 * 35 = $525
f ( 29 ) = 15 * 29 = $435
Week 1 : Ashley worked 35 hours. She earned $525.
Week 2: Ashley worked 29 hours. She earned $435.