1. Objective- To write a linear equation given a point
and a slope.
Write a linear equation in standard form given:
slope = y-intercept = -2
m = b = -2
y = mx + b
y = 3x + -2
Not in standard form!
-3x -3x
Ax + By = C
-3x + y = -2
Where A, B and C
are integers. or
3x - y = 2

2. No fractional coefficients!
Write a linear equation in standard form given: 2
slope = y-intercept = 4 3
y = mx + b 2
y = x + 4
Not in standard form! 3
Ax + By = C 2 2
- x x 3 3
Where A, B and C
are integers. 2
x + y = 4 3 2 3
x + y = 4
No fractional coefficients! 3
- 2x + 3y = 12
2x - 3y = -12 or

3. -1 (x,y) y = mx + b -1 -1 y = x + y = x + b -1 4 = (2) + b -2 4 = + b
Write a linear equation in standard form given: -1
slope = point = (2,4) 5
(x,y)
y = mx + b -1 22 -1
y = x +
y = x + b 5 5 5 1 1 -1
+ x x
4 = (2) + b 5 5 5 -2
4 = b 1 22 5
x + y = 5 5 5 2 2 5 5
x + 5y = 22 2 22
= b = 5 5

4. -11 -2 = (1) + b -11 -2 = + b -14 -11 -3 (x,y) y = mx + b -3 -3
Write a linear equation in standard form given: -3
slope = point = (1,-2) 7
(x,y)
y = mx + b -3
-11 -3
y = x +
y = x + b 7 7 7 3 3 -3
+ x x
-2 = (1) + b 7 7 7 -3
-2 = b
-11 3 7
x + y = 7 7 7 3 3 7 7
3x + 7y = -11 3
= b 7
-14
-11 3
= b = 7 7 7

5. -12 - x - x -3 -12 - - -3x + 5y = -12 -12 -12 (x,y) y = mx + b (4,0)
Write a linear equation in standard form given: 3
slope = x-intercept = 4 5
(x,y)
y = mx + b
(4,0)
-12 3
y = x + 3
y = x + b 5 5 5
- x x 3 3 3
0 = (4) + b 5 5 5 12 -3
-12
0 = b 5
x + y = 5 5 5 12 12 5 5
-3x + 5y = -12
-12
-12
= b = or 5 5
3x - 5y = 12

6. Slope Point Change in price = $7.50/ ft. 16 ft. cost $50 m = 7.50
A hardware store sells extension ladders. A 16 ft.
ladder costs $50 and the price increases $7.50 for
each additional foot. If x = ladder length and y = price,
write an equation for y in terms of x.
Slope
Point
Change in price = $7.50/ ft.
16 ft. cost $50
m = 7.50
(x, y) = (16, 50)
y = mx + b
y = 7.50x + b
y = 7.5x - 70
50 = 7.5(16) + b
50 = b
-70 = b