Answer:
Because X and Y vary directly, the equation is the form Y =KX. We can then solve for K by using the given values for X and Y. The equation that relates X and Y is Y= 5x
What do you mean by without calculating?
The answer is d because 2.25 times 4 equals 9 then 9 plus 14 equals 23
2c + b = 37 ....multiply by -3
4c + 3b = 81
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-6c - 3b = - 111 (result of multiplying by -3)
4c + 3b = 81
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-2c = - 30
c = -30/-2
c = 15 <== $ 15 for a can of paint
and it costs $ 7 for each brush
