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Question 1036636: This question is for linear functions.
y = 2x + 3
y= -3x - 2
I have to solve using elimination, I already tried but it came out wrong. I know the answer is (-1,1), because my teacher told me. I couldn't figure it out, please help me!
Found 2 solutions by JBarnum, jim_thompson5910:
Answer by JBarnum(2146)   (Show Source):
Answer by jim_thompson5910(35256)  (Show Source):
You can put this solution on YOUR website! y is equal to two different expressions, namely 2x+3 and -3x-2. Since the same y is equal to these two expressions, this means that the two expressions must be equal to each other
In other words, based on the given system we have this equation
2x+3 = -3x-2
Notice how I set the two right hand sides equal to one another.
Let's solve for x
2x+3 = -3x-2
2x+3+3x = -3x-2+3x
5x+3 = -2
5x+3-3 = -2-3
5x = -5
5x/5 = -5/5
x = -1
Now that we know x = -1, we can use this to find y. Pick any equation with x and y in it. Plug in x = -1. Simplify
Let's say we pick on the first equation
y = 2x+3
y = 2(-1)+3
y = -2+3
y = 1
So if x = -1 then y = 1
We can pick on the other equation
y = -3x-2
y = -3(-1)-2
y = 3-2
y = 1
and we get the same result
=================================================
So in the end, the solution to the system of equations is (x,y) = (-1,1)
Visually, this is where the two graphs cross.
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