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Perpendicular Lines

STEP 2: Use the point-slope formula with ( 1 , 3 )              and m = 5 / 2

y - y1 = m ( x - x1 ) ... y - 3 = 5 / 2 ( x - 1 ) ... multiply by 2, which gives 2 ( y - 3 ) = 2 ( 5 / 2 ) ( x - 1 ) ... 2y - 6 = 5 ( x - 1 ) ... 2y - 6 = 5x - 5 ... add 6 to both sides, which gives 2y = 5x + 1 ... y = ( 5 / 2 )x + 1 / 2
 

Graph 2x + 5y = 4 and y = ( 5 / 2 )x + 1 / 2 and see if they
really look perpendicular.

 

TRY IT:

Find the equation of the line that passes through the point ( -2 , 2 ) and is perpendicular to the line

3x - y = 1