Factor and check: y^2 -20y+91=0

y^2 -20y+91=0

(y )(y ) ( -13)( -7)=0

(y-13) (y-7) = 0

Check:

(y-13) (y-7) = 0

(y)(y) (y)(-7) (-13)(y) (-13)(-7)=0

y^2 -7y -13y +91

y^2 -20y +91=0