Subtraction of whole numbers is associative. Is this true or false. if false, please provide a counterexample.

Solve each quadratic equation by factoring and using the zero product property. x^2 - 8x + 30 = 3x

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?

Given the system of equations presented here: 2x + 4y = 14 4x + y = 20 which of the following actions creates an equivalent system such that, when combined with the other equation, one of the variables is eliminated? multiply the second equation by â’4 to get â’16x â’ 4y = â’80 multiply the second equation by â’1 to get â’4x â’ y = â’20 multiply the first equation by 2 to get 4x + 8y = 28 multiply the first equation by â’1 to get â’2x â’ 4y = â’14