Question 1131528
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The dimensions of the rectangle are x and 3x.


Also, the problem says that

(3x-2)*(x+3) = 42.


2x^2 - 2x + 9x - 6 = 42


2x^2 + 7x - 48 = 0.


Solve the quadratic equation; take the positive root - it will be the width.


Then evaluate the length as 3x.
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