Assuming you meant to write: "xy + zy" The answer is: xy + zy = y(x + z) The one variable that appear multiple times is: "y". There are no coefficients (other than the implied coefficients of "1"; since "1" multiplied by any number equals that very number). Since "y" appears twice, we can "factor out" a "y" ; as follows: ________________ y(x+z). ____________________ Take note of the distributive property of multiplication: _____________________ a(b+c) = ab + ac ; _________________ AND: a(b-c) = ab - ac. ____________________ Likewise: y(x+z) = yx +yz = xy zy ________________________
