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3 votes
Solve the quadratic equation by completing the square.

x^2+4x-6=0

First, choose the appropriate form and fill in the blanks with the correct numbers.
Then, solve the equation. Round your answer to the nearest hundredth.
If there is more than one solution, separate them with commas.

1 Answer

3 votes
1.16, - 5.16

Working
Take 6 to the other side
x^2+4x = 6
Find the 3rd for the left hand side:
x^2+4x+ (4/2)^2= 6 + (4/2)^2
Factoring the LHS gives
(x+2)^2=10
Finding square roots on both sides:
x+2=square root of 10
x+2= +3.1623 or - 3.1623
x=3.1623-2
=1.16
or
x= -3.1623 - 2
= - 5.16
User Jevon
by
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