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Can someone please help me omg (elimination method)

5x = y + 6
5x + 2y = 3 ​

User Shaymaa
by
4.6k points

1 Answer

5 votes

Answer:

The solution is (1, -1)

Explanation:

Rearrange the first equation so it is in standard form just like the second equation. To do this, subtract y from both sides.

5x = y + 6

-y -y

rewrite the equations

5x - y = 6

5x + 2y = 3

You have two choices of which variable ( x or y) you can eliminate. Regardless of choice you have to multiply one of the equations by a number. What you really want to look for is a set of twins, meaning you have the same number and the same variable. Also one has to be negative and one has to be positive. Both equations have a 5x, so I need to make one negative by multiplying the entire equation by -1. I'll do that with the top equation. This just changes the signs of each term.

-1(5x - y = 6)

-5x + y = -6

5x + 2y = 3

Add the two equations and solve for y. The -5x and 5x will now be eliminated. Remember there is a 1 in front of the y.

3y = -3

3y/3 = -3/3

y = -1

Now solve for x. Pick either of the original equations to substitute in for y. I'm going to pick the first one.

5x = y + 6

5x = -1 + 6

5x = 5

5x/5 = 5/5

x = 1

The solution is (1, -1)

User Kelvinji
by
3.5k points