I'm assuming you are asking 5x^2+7x = 6, and not 5*2 +7x = 6
We would use the quadratic formula to solve this.
5x^2+7x-6
(-7+-sqrt(7^2-4*5*-6))/2*5
(-7+-sqrt(49+120)/10
(-7+-sqrt(169)/10
(-7+-13)/10
-20/10=-2
6/10=3/5
So the answer is B) x = –2 or x = 3/5