SOLUTION: Given line L: y=2x-3. What is the gradient of a line which is perpendicular to L? Could someone help me? I don't get how the answer's not 2. Thanks :)

Algebra ->  Graphs -> SOLUTION: Given line L: y=2x-3. What is the gradient of a line which is perpendicular to L? Could someone help me? I don't get how the answer's not 2. Thanks :)      Log On


   

Question 1016729: Given line L: y=2x-3. What is the gradient of a line which is perpendicular to L?
Could someone help me? I don't get how the answer's not 2. Thanks :)
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the gradient is the slope.

your line is y = 2x - 3
the slope is 2 and the y-intercept is -3.

another line parallel to y = 2x - 3 would have same slope and a different y-intercept.

another line perpendicular to y = 2x - 3 would have a slope that is the negative reciprocal of 2.

that makes the slope equal to -1/2.

a line parallel to y = 2x - 3 could be y = 2x + 3.

a line perpendicular to y = 2x - 3 could be y = -1/2 * x + 3.

here's what they look like on the graph.

red is the original equation of y = 2x - 3

blue is the parallel equation of y = 2x + 3

green is the perpendicular equation of y = -1/2 * x + 3

the y-intercepts are the intersection of the lines with the y-axis.




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