First, simplify the numerator:
x+y7+61=6(x+y)7(6)+1(x+y)=6(x+y)42+x+y Next, simplify the denominator:
x+yx−1=x+yx−(x+y)=x+yx−x−y=x+y−y Now we have:
x+y−y6(x+y)42+x+y To simplify this complex fraction, we multiply the numerator by the reciprocal of the denominator:
6(x+y)42+x+y⋅−yx+y=6(x+y)(−y)(42+x+y)(x+y) We can cancel out the (x+y) term in the numerator and denominator, assuming x+y=0: 6(−y)42+x+y=−6y42+x+y=−6yx+y+42