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A line through points (4,2) and (0,0) is perpendicular to a line through points (0,-2) and (x,4). What is the value of x?​

User TinsukE
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1 Answer

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Answer:

x = -3

Explanation:

The slope of the line through the given points is ...

m = (change in y)/(change in x) = (2-0)/(4-0) = 1/2

The slope of a perpendicular line will be the negative reciprocal of this:

perpendicular slope = -1/m = -1/(1/2) = -2

The point given on the perpendicular line is its y-intercept, so we can write the equation of the line in slope-intercept form as ...

y = -2x -2

For y=4, the corresponding value of x is the solution to ...

4 = -2x -2

6 = -2x . . . . . . add 2

-3 = x . . . . . . . .divide by -2

The perpendicular line goes through points (0, -2) and (-3, 4).

A line through points (4,2) and (0,0) is perpendicular to a line through points (0,-2) and-example-1
User Dimsuz
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