1. Writing Linear Equations Using Slope Intercept Form

2. Slope-Intercept Form
y = mx + b (c) [or f(x) = mx + b]
m is the slope/gradient
b/c is the y-intercept

3. Find the Equation of the Line
What is the
y-intercept?
b = -2
What is m?
m =
y = x -2 x y

4. Find the Equation of the Line
b = ?
b = 1
m = ?
m = -
y = - x + 1 x y

5. Find the Equation of the Line
b = ?
b = 4
m = ?
m = 0
y = 0x+4
y=4 x y

6. Find the Slope and y-intercept of each Equation:
1) y = -4x + 3
m = -4
b = 3
2) y = x
m = -
b = 5
3) 8x + y =
m = -8
b =
4) 4x - 2y = 10
m = 2
b = -5

7. Find the Equation Given the Slope and y-intercept
1) m = -3, b = 1
y = -3x + 1
2) m = - , b = -4
y = - x - 4

8. Find the Equation Given the Slope and a Point
Given m = -1, (2, 1)
First, calculate b by substituting the slope and the coordinates into y = mx + b.
y = -1x + b
1 = -1(2) + b
1 = -2 + b
3 = b
y = -1x + 3

9. Write the equation. gradient = 2, passes through (-4, 6)
slope = -3/2, passes through (5, 3)

10. Find the Equation Given Two Points
Given (-1, 3) and (2, 1)
First, calculate the slope:
Second, find b. Use either point...
m = , (2, 1)
1 = (2) + b
1 = b
= b

11. Write the equation passes through (6, 1) and (8, -4)