Question 167450
The approach is WRONG.
Proof:
7^2+7-6=5
49+7-6=5
50=5 is an invalid proof.
2^2+2-6=5
4+2-6=5
0=5 is another invalid proof.
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The proper solution follows:
x^2+x-6=5
x^2+x-6-5=0
x^2+x-11=0
{{{x=(-b+-sqrt(b^2-4*a*c))/(2*a)}}} 
x=(-1+-sqrt[1^2-4*1*-11)/2*1
x=(-1+-sqrt[1+44])/2
x=(-1+-sqrt45)/2
x=(-1+-6.7082)/2
x=(-1+6.7082)/2
x=5.7082/2
x=2.8541 answer.
x=(-1-6.7082)/2
x=-7.7082/2
x=-3.8541 answer.