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Find an equation of the line perpendicular to y = - 2x + 2

through the point (2,2). Graph the lines.

User Trickbz
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1 Answer

5 votes

Answer:

y = (1/2)x + 1

Explanation:

y=mx+b, where m is the slope and b the y-intercept (the value of y when x = 0). We are given y = -2x + 2 as the reference line and are asked to find a line that is perpendicular to it. (We'll get to the (2,2) thing later).

A perpendicular line has a slope that is the negative inverse of the reference line slope, which in this case is -2 (the m). The negative inverse of -2 is -(-1/2) or (1/2), This measn the perpendicular line will have the form:

y = (1/2)x + b

The complication is that we want this new line to go through point (2,2). Easy. Just substitute (2,2) in the aboove ea=quation and solve for b:

y = (1/2)x + b for (2,2)

2 = (1/2)2 + b

b = 2 - 1, b = 1

The equation of the line perpendicular to y = -2x + 2 is y = (1/2)x + 1,

See attached graph for proof.

Find an equation of the line perpendicular to y = - 2x + 2 through the point (2,2). Graph-example-1
User Diann
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