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Solve the equation for all values of x by completing the square.
x2 + 16x - 40 = 0

User Urho
by
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1 Answer

3 votes

Answer: x=(±2√21)-8

Explanation:

Add 104 to both sides so we can get x^2+16x+64

x^2+16x+64=104

then factor

(x+8)^2=104

square root both sides

x+8=±√104

simplifying the radical and subtracting 8 gets us this

x=(±2√21)-8

Hope this helps!

User Tbaki
by
8.3k points