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5 votes
This is Josh’s solution for the equation

x2-6x-7=0:

x2-6x-7=0
x2-6x=7
x2-6x+9=7+9
(x-3)2=16
x=19
x-3=-16
x=-13
Is Josh’s solution correct? Explain

1 Answer

6 votes
No. After completing the square, Joshua should have taken the square root of the equation. As a result, he should have gotten:

x - 3 = 4 OR x - 3 = -4

And the result answer would have been x = 7 or x = -1
User Sloneorzeszki
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