For this problem, use the FOIL method First, outer, inner, last First, multiply the first term with the third term, 2x times x is 2x^2 Next, multiple the first term with the last term, 2x times 7 is 14x Now, multiply the second term with the third term, -5 times x is -5x Then, multiply the second term with the fourth term -5 times 7 is -35 Finally add all these answers up - 2x^2+14x+(-5x)+(-35) Combine like terms to get your answer 14x+(-5x)=9x 2x^2+9x-35
Jack's method is equivalent because of the "law of commutative property", which means that multiplication problems have the same result no matter the order.
