Question

Find an equation of the line that passes through the points (1 2) and perpendicular to the line 2y-x=4

Answer 1

Steps to find the equation
1. Find the slope
2. Insert slope into the general equation
3. Find y-intercept
4. Insert -intercept into the equation found in step 2
And you get the equation of the line

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Find the slope
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2y - x = 4

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Rewrite into the form y = mx + c
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2y = x + 4
y = 1/2 x + 2

Slope = 1/2
Perpendicular slope = -2 (negative reciprocal)

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Insert slope into the equation
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y = mx + c
y = -2x + c

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Find y-intercept
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y = -2x + c
At point (1, 2)
2 = -2(1) + c
2 = -2 + c
c = 4

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Insert y-intercept into the equation y = -2x + c
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y = -2x + 4

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Answer: y = -2x + 4
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