Answer: w = 5
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Step-by-step explanation:
The term wy^2 out front multiplies with each term inside the parenthesis (because of the distributive rule).
Let's multiply the outer term with the first term inside the parenthesis to get the following:
wy^2 times 8y^3 = 8wy^5
Compare 8wy^5 with 40y^5, and we see the coefficients 8w and 40 match up. Therefore, 8w = 40 solves to w = 5