Download 5.5 Writing Equations in Point-Slope Form

Reteach Chapter 4
Linear Equations
Forms of lines
Slope-intercept form:
“y by itself”
y = mx + b
Standard form:
Ax
“x and y alone on the left”
Point-slope form:
Slope Formula
+ By = C
y – y1 = m (x - x1)
y2 – y1
x2 – x1
Ex 2 Write the point-slope form of an equation
3
for a line that passes through (-2,0) with slope 
2
(y - y1) = m (x - x1)
3
y  0    x  (2) 
2
3
y   ( x  2)
2
Ex. 1 Write an equation in slope intercept form if
2
y  7   ( x  3)
3
2
y7   x2
3
2
y   x5
3
Ex. 2 Write an equation in standard form
y  3  4  x  2  Don’t forget to
y  3  4 x  8
3
3
y  4 x  5
4x 4x
4x  y  5
distribute the
negative!!!!
Ex.5: Write in standard form
3
y  3   ( x  7)
4
3 21
y 3  
4
4
4 y  12  3 x  21
12
12
4 y  3 x  9
3x 3x
3x  4 y  9
Ex 6. Find the equation of the line passing through
2
(-3,-1) with slope 
3
a) Write the equation in point-slope form
2
y  1   ( x  3)
3
b) Write the equation in slope-intercept form
2
y   x3
3
c) Write the equation in standard form
2 x  3 y  9
Ex 7 Identify the slope of the following equation and
then identify the parallel and perpendicular slopes.
1
y  x7
2
1
m
2
1
m
2
2
m
1
 2
Ex 8 Write the slope-intercept form of a line
through (7, -1) and parallel to the graph of
2
y  y1  m( x  x1 )
y  x 5
7
2
y  1  ( x  7)
2
7
m
7
2
y 1  x  2
2
7
m
7
1
1
2
y  x 3
7
Ex 9 Write the slope-intercept form of a line
perpendicular to the graph of 2y + 5x = 2 that
passes through (0, 6).
y

y

m
(
x

x
)
1
1
2 y  5x  2
2
5x 5x
y  6  ( x  0)
5
2 y  5 x  2
2
2
2 2
y

6

x

0
5
5
y   x 1
2
5
m
2
2
m
5
6
6
2
y  x6
5
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