A math student has a plan to solve the following system by the elimination method. To eliminate the x-terms, he wants to multipl
y the top equation by 7. What should he multiply the second equation by so that when he adds the equations, the x-terms are eliminated?
-3x-7--56
-7x+10y - 1
because the eq. multiplied by 7 is negative, the second eq mus be positive in order to eliminate the x variable. this is why we multiply by a (-). by multiplying the second eq by 3, both eq. will result in a coefficient of 21. one positive one negative allowing the x variable to be eliminated from the problem.
