Page 55 - Math Course 2 (Book 2)

Parallel and Perpendicular Lines

Perpendicular Line Through a Given Point
Step 3 Substitute the slope and the given point
into the point-slope form of a linear
equation. Then write the equation in Write the slope-intercept form for an equation of
slope-intercept form. a line perpendicular to the graph of y = 2x + 1 that

y – y = m(x – x ) Point-slope form passes through the x-intercept of that line.
1 1
2 Replace x with 0, y with 6,
y – 6 = (x – 0) 1 1
5 and m = – 2 A. y = 2x – 1
5
2
2
y = x + 6 Distributive Property
5 1 1
B. y = – x – 4
2
The equation of the line is
Answer 2 1
y = x +6 C. y = –2x –
5 4
1 1
D. y = – x – 2
2
Your Turn! Answer

Perpendicular Line Through a Given Point

Write the slope-intercept form for an equation of a
line that passes through (–3, 6) and is
perpendicular to the graph of 3x + 2y = 6.

3
A. y = – x + 8
2
2
B. y = – x + 6
3

C. y = –3x + 8

2
D. y = x + 8
3

Answer

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