# pre algebra

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how do i solve systems?
example- y=x-2 y=4x+1

• pre algebra -

set y = y
4x + 1 = x - 2

you finish it.

• pre algebra -

Multiple the first equation by -1:
-y=-x+2

Add it from the second one to get:
y=4x+1 +(-y=x+2)= 0=3x+3

Subtract 3 from both sides:
-3=3x

Divide by 3
x=-1

Plug it in for one equation:
y=(-1)-2

y=-3

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