4. Sundar used linear combination to solve the system of equations shown. He did so by multiplying the first equation by 5 and the second equation by another number to eliminate the y-terms. What number did Sundar multiply the second equation by?

2x + 9 = 41

3x + 5y = 36

If he multiplied the first equation by 5, that would give us:

10x + 45y = 205

Now we need to get - 45y to eliminate the y-terms, So we divide - 45 / 5 and we get - 9. So we multiply the 2nd equation by - 9.

(I'm assuming the first equation is actually 2x + 9y = 41, and not 2x + 9 = 41)