Question

I don't know what number to multiply these coefficients by to be able to cancle and combine! HELP!

Answer 1

we have

x-y=100 ------> equation A

(3/8)x+(7/8)y-2000 -------> equation B

Multiply equation A by 7/8

so

(7/8)x-(7/8)y=700/8

adds equation B