Let the number = x
Writing the equation you have:
10x + 15 <= -17
Solve for x
Subtract 15 from both sides:
10x <= -32
Divide both sides by 10:
X <= -32/10
Simplify:
X <= -16/5 as a fraction or -3.2 as a decimal
EGD, the sides look the same
M represents the month because the value is decreasing every month.
Hope this helps :)
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