What is the equation of the line that passes through the point (6,-1) and has a slope of 1?

y

=

4

3

x

−

9

Explanation:

Given -

x

1

=

6

y

1

=

−

1

Slope

m

=

4

3

Given the slope and a point, the formula for the straight line equation is

(

y

−

y

1

)

=

m

(

x

−

x

1

)

y

−

(

−

1

)

=

4

3

(

x

−

6

)

y

+

1

=

4

3

x

−

6

.

4

3

y

+

1

=

4

3

x

−

8

y

=

4

3

x

−

8

−

1

y

=

4

3

x

−

9

f(x) has value 150 at x= 0

and 0 at x= 3

so d(f(x))/dt = slope = -150/3 = -50