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View Full Version : How do I use substitution to solve each system of equations

teslarose
Oct 28, 2008, 04:24 PM
x=7y-4
2x-3y=14

:confused:


can you help me?
justcurious55
Oct 28, 2008, 06:47 PM
2(7y-4)-3y=14
14y-8-3y=14
11y-8=14
+8 +8
11y=22
/11 /11
y=2

x=7(2)-4
x=14-4
x=10

(10,2)

you plug x into the equation. You literally substitute what comes after "x=" for x in the second equation. Hope this helps