Question 207926
always two line will intersect only once.
if they have the same y intercepts then that is their point of intersection.
example:
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y = -2x + 3
y = 1/2x + 3
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these lines are perpendicular because their slopes are negative reciprocals of each other.
as can be seen on the graph, their only point of intersection is at the y intercept.
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{{{graph(600,600,-5,5,-5,5,-2x+3,(1/2)x+3)}}}