I am mainly struggling with problem 2. I found this in an Electricians Book and am confused on the steps for their answer. I'll figure it out soon I'm sure but am still confused.
I am new to this site and am not all that great at math but am trying to grow. I can't figure out how to work these equations.1) x + y + z = 15
5x - z = 18
4y + z = 19In this one I need to solve for the variables. the answers for x, y, z are 5,3,7
2) l1 + l3 = l2
5.2l1 - 3.25l2 = (-12.35)...