9.2 Solve -a2b-a2x-ab2-2abx-ax2-b2x-bx2 = 0
In this type of equations, having more than one variable (unknown), you have to specify for which variable you want the equation solved.
W+D=659
W=D-91
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(D-91)+D=659
D-91+D=659
2D=750
D=750/2=375
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W+375=659
W=284
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So the dryer had cost $375 and the washer had cost $284.
Answer is A.
step 1 , 16 was not multiplied by 9
should be
54x - 9y = 144
Well the answer would be 8 as the total sum would be 6 x (8) = 48