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2x- y = -1
5x + 4y = 17

User Sreekumar
by
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1 Answer

6 votes
Answer:

You will need to use simultaneous equations.

Method:

Get both equations to have the same subject, in this case we will multiply the first equation by 4

1) 2x-y = -1
Becomes
1) 8x-4y = -4

Then make both equations equal to 4y.

1) 8x+4= 4y
2) 4y = -5x + 17

Because they both equal 4y, that means they are equal to each other.

8x+4 = -5x+17
Now solve for x.

13x = 13
x = 1

Now that we have x, we can substitute it back into either equation to get y. I will use equation 1 because it is less complex.

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

User Digglemister
by
3.1k points