Finding Slope of a Line
Evaluate:
-2 - 5
-7
What form of equations do we use for straight lines?
y = mx + b or slope intercept form.
Identify the slope of the following equation.
y = 2x + 3
slope is 2
When graphing linear equations, where do we begin?
We begin at the y-intercept or b.
In the following linear equation, what is the y-intercept?
y = -3/4x
0
Solve:
3x - 2 = -14
x = -4
Write an equation for a vertical line through the point (-3, 3) (hint: y=? or x=?)
x = -3
What is the slope of a vertical line?
undefined of course
Which graph has a steeper slope?
A.) y = 3x + 4
B.) y = 1/3x + 4
A.
Rewrite this equation in slope-intercept form.
x + y = -12
y = -x - 12
What is the slope of this equation?
x = 5
Undefined Slope
What is the slope of this line?
y = 5 + 2/3x
slope = 2/3
m = 2/3
Find the slope of the line that includes the following points.
(4, -5) (-4, 5)
-10/8 which simplifies to -5/4
The graph of the following equation is vertical or horizontal?
y = -2
horizontal
Rewrite the following equation in slope-intercept form. 3x + 6y = -18
y = -1/2x - 3
Graph the following equation. y=-2x+4
(Teacher check graphs)
What is the slope of a line that goes through these two points?
(15, -10) (5, 10)
slope = -2
or m = -2
Find the slope of the line that includes the following points.
(-12, -9) (-3, -3)
-6/-9 = 6/9 = 2/3
Do these graphs have the same slopes?
y = 1/2 x +5
y = 1/2x - 5
Yes
m = 1/2
Rewrite the following equation in slope-intercept form.
35x - 7y = -21
y=5x+3
Is x = 2 a solution to the equation 2(x - 5) + 3 = 13 ?
No it is not a solution.
The amount y(in dollars) of money you have left after playing x games at a carnival is y = -0.75x + 10. How much money do you have after playing eight games?
$4 dollars left after playing 8 games.