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Uhhh, a little help?!?

Uhhh, a little help?!?-example-1
User Palladin
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1 Answer

3 votes

Answer:

(c) x = 1, y = -2.

Explanation:

I am not going to solve them all for you but the method of elimination is applicable to all these systems.

I'll do question c:

First, to make things easier we arrange each equation to the form ax + by = c:

y - x = -3 so

-x + y = -3..............(1)

(2x + y) / 2 = x - 1:

2x + y = 2x - 2

2x - 2x + y = -2

y = -2

Now multiply both sides by -1 so we can eliminate y by adding to equation (1):

-y = 2...................(2).

Now if we add equations (1) and (2) we eliminate y:

-x + y - y = -3 + 2

-x = -1

x = 1 is one solution.

Finally we find the value of y by substituting x = 1 in the original equation

y - x = -3

y - 1 = -3

y = -3 + 1

y = -2.

User Andrew Fleenor
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