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A math student has a plan to solve the following system by the elimination method. To eliminate the x-terms, he wants to multiply 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

Respuesta :

Answer:

-3

Step-by-step explanation:

7(-3x-7y-56)

-21x-49y-392

-3(-7x+10y-1)

21x-30y+3

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.