Question 662946
4.50/hr for fence
6.50/hr for grass
4.50x + 6.50y = 39.50
x+y=7
Substitute into the first equation
4.50(7-y) + 6.50y = 39.50
31.50 - 4.50y + 6.50y = 39.50
31.50 + 2y = 39.50
2y = 39.50 - 31.50
2y = 8
y = 4 hours mowing grass
x = 7-4= 3 hours painting the fence
Proof
4.5(3) + 6.5(4) = 
13.50 + 26 = 39.50
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