Given the following system of equations, what number should you multiply the first equation by so that the x-term will be eliminated when the first equation is added to the second equation?

Question

4x - y + 7z = 65

x + 9y - 5z = - 24

- 7x + 4y - 2z = - 5

Thank you!

Answer 1

Let k be the mulitplier

You want 4k+1 = 0 when adding equation one to equation two.

k = -1/4