SOLUTION: i don't understand substitution or elimination.

Algebra ->  College  -> Linear Algebra -> SOLUTION: i don't understand substitution or elimination.      Log On


   



Question 66406: i don't understand substitution or elimination.
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
using the substitution method involves the following:
x+y=3 so x=3-y then we substitute (3-y) for x -n equation 2
2x+3y=8
2(3-y)+3y=8
6-2y+3y=8
y=8-2
y=2 solution now substitute 2 for y & solve for x
x+2=3
x=3-2
x=1 solution.
-------------------------------------------------------------------------
using the elimination method involves the following:
2x-5y=11
3x+5y=4 adding the 2 equations we eliminate the y values & we get
------------------------------
5x=15
x=15/5
x=3 solution
2*3-5y=11
6-5y=11
-5y=5
y=5/-5
y=-1 solution.