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10 votes
10 votes
11.) SOLVE the equation for w by using "factoring by grouping". YOUMUST SHOW ALL STEPS of the grouping process, especially theFIRST STEP of grouping to receive FULL CREDIT. (10 pts)2w3 + 5w2 - 32w - 80 = 0

User Milos Kovacevic
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1 Answer

23 votes
23 votes

ANSWER:

w = -5/2, w = 4 and w = -4

Explanation:

We have the following equiation:


2w^3+5w^2-32w-80=0

We solve with the help of factoring by grouping


\begin{gathered} (2w^3+5w^2)+(-32w-80)=0 \\ w^2\cdot(2w+5)-16\cdot(2w+5)=0 \\ (2w+5)\cdot(w^2-16)=0 \\ 2w+5=0\rightarrow w=-(5)/(2) \\ (w^2-16)=0\rightarrow w^2=16\rightarrow w=\pm4\rightarrow w=4,w=-4 \end{gathered}

The solutions are w = -5/2, w = 4 and w = -4

User Wmli
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