Question 678325
A. 20x + 10y = 500
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B. 10y = -20x + 500
y = {{{(-20/10)x + 500/10}}}
y = -2x + 50
y intercept is 50
x intercept is where y = 0
0 =-2x+50
-50=-2x
x = 25
x intercept is 25
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C.  The intercepts indicate how many hours must be worked on one job without working any hours on the other job.
y intercept of 50 means, 50 hours of y, washing windows, with 0 hours of mowing.
x intercept of 25 means, 25 hours of x, mowing, with 0 hours of washing windows
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D. {{{graph(300,200,-5,30,-5,55,-2x+50)}}}
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E. If y = 30, then x = ?
30 = -2x+50
2x = 50-30
2x = 20
x = 10 hours mowing
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