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4 votes
Elimination method

-2x+y=-8
2x+4y=18

User Peppe
by
6.8k points

2 Answers

3 votes
elimitation method
basically eliminate one of the terms completely
we see that there is a -2x and a 2x in the 2 equations
so just add them together
2x-2x+4y+y=18-8
5y=10
divide both sides by 5
y=2

subsitute
-2x+2=-8
subtract 2 form boht sides
-2x=-10
divide both sides by 2
-x=5
multiply -1
x=5

y=2
x=5
User Gandharv Garg
by
6.8k points
2 votes
We have to add first eq to second eq.
-2x+y+2x+4y=-8+18
5y=10 /:5
y=2
Now we can backsubstitute
2x+4*2=18
2x+8=18 /-8
2x=18-8
2x=10 /:2
x=5
Finally we obtain result
x=5
y=2
User John Ellmore
by
6.7k points