2006-10-08 05:16:21 · 3 answers · asked by Tammy M 2 in Education & Reference ➔ Homework Help
addition:
5x-4y = -5 -multiply one of them by something so you can
x-2y= -7 easily add or subtract them
5x-4y= -5 -add/subtract to get rid of a variable
-(2x-4y= -14)
_________
3x + 0y=9
3x = 9 -so, x = 3..... now go back, plug it in to either problem to solve for y
5x-4y= -5
5(3)-4y= -5
15-4y = -5
-4y= -20
y=5
SUBSTITUTION:
simply plug one equation into the other
make x-2y= -7 turn into x= 2y-7
go to the other equation, and plug in x
5x-4y= -5
5(2y-7)-4y= -5
10y-35-4y= -5
6y-35= -5
6y = 30
y = 5
now plug in y as = 5
x-2y= -7
x-2(5)= -7
x-10= -7
x=3
2006-10-08 05:24:30 · answer #1 · answered by Anonymous · 0⤊ 0⤋
X= 7/15 and Y= -7/3. Hey, you should not pose your homework here.
2006-10-08 05:23:12 · answer #2 · answered by Trad 2 · 0⤊ 0⤋
i got 10x=2y= -7 idk how you were tought
2006-10-08 05:19:27 · answer #3 · answered by alejandra611 2 · 0⤊ 0⤋