Answer:
Explanation:
x^2-6x=7 is our equation
x^2-2*3*x= 7
So the term we will be adding is 3^2 since 3 the second term is 2*3*x
x^2-6x+9=7-9
We added 9 and substract it to keep the equation
(x+3)^2 = -2
Wich is impossible since a squared number is always positive