Verified answer

x^2+6xy-7y^2 = (x + )(x - )

to get x^2 you need x and x. You know the factors of - 7 are 1 and 7 and one of them has to be negative to get -7. They have to add up to +6 so we need +7 and -1. y*2 factors into y and y

x^2+6xy-7y^2 = (x + 7y )(x - y)