If bracket x plus 6 times bracket x minus 7 equals the square of x plus ax plus B, then what does a equal and what does B equal?

If bracket x plus 6 times bracket x minus 7 equals the square of x plus ax plus B, then what does a equal and what does B equal?

(x + 6) * (X-7) = the square of X + ax + B
6x-42 + square of x-7x = square of X + ax + B
X = - ax-b-42
a= -1 ,b= -42