Objective To write a linear equation given a point

1
Objective- To write a linear equation given a
point and a slope.
Write a linear equation in standard form given
slope 3 y-intercept -2
m 3 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
Write a linear equation in standard form given
2
slope y-intercept 4
3
y mx b
2
Not in standard form!
y x 4
3
Ax By C
2
2
- x - x
Where A, B and C are integers.
3
3
2
- x y 4
3
2
- x y 4
3
No fractional coefficients!
3
2x - 3y -12
- 2x 3y 12
or
3
Write a linear equation in standard form given
-1
slope point (2,4)
5
(x,y)
y mx b
-1
22
y x
-1
y x b
5
5
5
1
1
-1
x x
4 (2) b
5
5
5
-2
22
4 b
1
5
x y
5
5
5
2
2

5
5
x 5y 22
2
22
4 b

5
5
4
Write a linear equation in standard form given
-3
slope point (1,-2)
7
(x,y)
y mx b
-11
-3
y x
-3
y x b
7
7
7
3
3
-3
x x
-2 (1) b
7
7
7
-3
-11
-2 b
3
7
x y
7
7
7
3
3

7
7
3x 7y -11
3
-2 b
7
-14
-11
3

b
7
7
7
5
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
3
3
- x - x
3
0 (4) b
5
5
5
-12
12
-3
0 b
5
x y
5
5
5
12
12
- -
5
5
-3x 5y -12
-12
-12
0 b

or
5
5
3x - 5y 12
6
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
50 120 b
-120 -120
-70 b