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1 vote
Solve by completing the square. 4x²-8x-32=0

User Chiara Ani
by
4.8k points

1 Answer

6 votes

Answer:

4, -2

Explanation:

Hello, please consider the following.


\begin{aligned}4x^2-8x-32=0 &\text{ ***We divide by 4.***}\\\\x^2-2x-8=0 &\text{ ***We complete the square. ***}\\\\(x-1)^2-1-8=(x-1)^2-9=0 &\text{ ***We move the constant to the right.***}\\\\(x-1)^2=9=3^2 &\text{ ***We take the root.***}\\\\x-1=\pm3 &\text{ ***We add 1.***}\\\\x=1+3=\boxed{4} \ & or \ x=1-3=\boxed{-2}\end{aligned}

Thanks

User Tielman Nieuwoudt
by
5.3k points
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