Use substitution to solve the system of equations.
5x + 5y = -30
2x - y = 15....
Question 2....
Use substitution to solve the system of equations given by y = 2x and 5x + y = 7...
Thank you all!
2007-02-13 19:17:53 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
Well, in question 2 you have y = something. So in the other equation substitute 5x + something = 7, and solve for x. Once you know x,, calculate y = 2*x.
Same idea in question 1. Start with y = 2x - 15, and proceed from there. Of course, 5x + 5y = -30 is easier to deal with if you divide both sides by 5.
2007-02-13 19:36:25 · answer #1 · answered by Curt Monash 7 · 0⤊ 0⤋
1) from the second you get y=2x-15.So go to the first and
5x+10x-75 =-30 so 15x= 45 and x= 3 y = -9
You can do the second
2007-02-13 22:13:17 · answer #2 · answered by santmann2002 7 · 0⤊ 0⤋
y=-9
y=2
2007-02-14 01:26:03 · answer #3 · answered by elizabeth q 1 · 0⤊ 0⤋