Question

Solve by using elimination:

7x - 2y =3
2x +y = 4

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Answer 1

(1) 7x - 2y =3
(2) 2x + y = 4

look to see which variable is easier to get rid of. since the first equation has -2y, multiple the 2nd equation by 2, so that you get 2y. -2y + 2y = 0, so you will have eliminated the y variable

Multiple (2) by 2
2 (2x + y = 4) = 4x + 2y = 8

Add the two equations together
7x - 2y = 3
4x + 2y = 8
11x + 0 = 11
11x = 11
x = 1

Substitute x = 1 in either equation (1) or (2) to find y.

7x - 2y = 3
7(1) - 2y = 3
7 - 2y = 3
2y = 4
y = 2

To check
substitute x = 1, y = 2
in the other equation (1)
2x + y = 4
2(1) + 2 = 4
2 + 2 = 4
4 = 4
so it's correct

Answer 2

Thanks a lot:D

Answer 3

you're welcome