Answer:
36
Step-by-step explanation:
first, see the formula in the attached picture.
now, by applying that formula we get :
the coefficient of the x7y2 is :
9C7 = 36 (you can either use a calculator or just the algebraic formula)
0.4 gallons * 4.2 hours = 1.68 gallons
Gabriel uses 1.68 gallons in 4.2 hours.
X is 4 y is zero. So he can do four math assignments if this doesn't include breaks.
Answer: C
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