Answer: Choice B
(-2, 5)
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Explanation:
The original system is

Multiply both sides of the second equation by 3. Doing so leads to this updated system of equations

Now add straight down
The x terms add to -4x+3x = -1x = -x
The y terms add to 3y+(-3y) = 0y = 0
The terms on the right hand sides add to 23+(-21) = 2
We end up with the equation -x = 2 which solves to x = -2
Now use this to find y. You can pick any equation with x,y in it
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-4x+3y = 23
-4(-2)+3y = 23
8+3y = 23
3y = 23-8
3y = 15
y = 15/3
y = 5
Or
x-y = -7
-2-y = -7
-y = -7+2
y = -5
y = 5
Either way, we get the same y value.
So that's why the solution is (x,y) = (-2, 5)
With mental math, you can perform equations quickly and efficiently. They also help you to develop your own strategies and solve more complex math equations. Hope this helps;)
Well... the segment FG = 4x + 3, the segment GH = 7x - 12, now, the
segment FH = FG + GH, those two fellows added up, and we know that FG and GH are both equal halves because G is the midpoint.
thus, FG = GH
or

and fairly sure, you know how much that is.
Answer:
38-15c-4
Step-by-step explanation:
38-x=12c+4+3c
38-x=15c+4
x=38-15c-4