Download Lesson 3.3

College Algebra: Lesson 3.3 Forms of Linear Equations
Recall:
1. Slope Intercept Equation: y = mx + b (m = slope, b = y-intercept)
2. Point Slope Equation: y  y1  m( x  x1 ) , where m = slope and ( x1 , y1 ) is a point on the line
3. Standard form: ax + by = c
rise y 2  y1
4. Slope: m 
; where ( x1 , y1 ) and ( x2 , y2 ) are points on the line

run x2  x1
#
0
 0 and  undefined ; If the slope is 0, it's a horizontal line, y = #. If the slope is undefined, it's a
5.
#
0
vertical line, x = #.
Examples:
1. Write the slope intercept form of the equation for the line that passes through the point (0,9) and has a slope
of 2.
2. Write the slope intercept form of the equation for the line that passes through the point (7, 2) and has a slope
of -4/3.
3. Find the slope of the line determined by the equation
a. 4x - 5y = 24.
b. 7y = 1
4. Determine the slope of the line that passes through the points
a. ( -6, 1 ) and (-4, 1)
b. (-4,5) and (-4,-2).
c.
x y
 21
3
5. Write the standard form of the equation of the line that passes through the points:
a (0,-7) and (0,10)
b. (0,-12) and (5,11)
6. Graph the linear equation. Determine the slope and y-intercept of the equation.
3
x3
a. y 
4
7. Graph the line determined by the equation:  3x  2 y  36  0 .
Step 1: Write in slope intercept form
Step 2: Given x = - 10, enter the value of y
Step 3: Given x = -8, enter the value of y.
8. Graph the line determined by the equation 2x - 6 = 0.
Step 1: Write the equation of the line by solving for x.
Step 2: Given y = -2, find the corresponding
x-value.