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- 6x - 2y = 20 \\ 2x - y = 0
I need to solve it by elimination

User Rebeku
by
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1 Answer

5 votes
First equation
-6x - 2y = 20
Second equation
2x - y = 0

By elimination method, we need to eliminate one of the variable.

First Elimination
I want to remove y-variable to find the value of x, so multiply the first equation by 1 and multiply the second equation by 2.
-6x - 2y = 20 (multiply 1)
2x - y = 0 (multiply 2)
---------------------------------
-6x - 2y = 20
4x - 2y = 0
-------------------- - (substract)
10x = 20
x = 2

Second Elimination
I want to remove x-variable to find the value of y, so multiply the first equation by 1 and multiply the second equation by 3.
-6x - 2y = 20 (multiply 1)
2x - y = 0 (multiply 3)
----------------------------------
-6x - 2y = 20
6x - 3y = 0
------------------ + (add)
-5y = 20
y = -4

The solution is (x,y) = (2,-4)
User Rannie
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7.3k points