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5 votes
Find the point where two lines intersct

2 Answers

1 vote
y=2x+3
y=-x
To find the point, first set them equal to each other:
2x+3=-x
Then, solve for x:
3x=-3
x = -1
y = -x --> y = -(-1) = 1
So the point is (-1,1)
User Victor Motogna
by
5.7k points
4 votes
y=2x+3
y=-x
the interssection is the set of points that make both systems true

set them eual to each other since they both equal y
2x+3=y=-x
2x+3=-x
add x to both sides
3x+3=0
subtract 3
3x=-3
divid 3
x=-1

subsitue
y=-x
y=-(-1)
y=1


(x,y)
the intersection is (-1,1)