X+2y=1
X-y=-5
Assuming you are looking for "Point" of intersection:
Choose one, solve for "x"
add y to both sides of equality:
X-y=-5
+y +y
X=y-5
Now replace "y-5" for "X" in the other equation:
X+2y = 1
(y-5)+2y = 1
y-5+2y = 1
Combine "y" (Add)
3y -5 = 1
Add 5 to both sides of equality:
3y -5 = 1
+5 +5
Divide both sides by 3 to solve for y:
3y = 6
(3y)/3 = (6)/3
y = 2
We have found "y" but this is not a 2D point. We need an "X".
Choose one of the top two equations:
X-y=-5
Substitute "2" for "y" because we found "y=2":
x-2=-5
Add "2" to both sized of equalty:
x-2=-5
+2 +2
x = -3
We have found "x"
Now, answer in "Point Format"
P(x,y)=P(-3,2)
These two equations for lines (X+2y=1) and (X-y=-5) intersect at point P(x,y)=P(-3,2)
HTH
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