Question

( 3, 8 ) and ( 1 , 3 ) what is the slope , point slope , and slope intercept ?

Answer 1

The formula of a slope:

`m=(y_2-y_1)/(x_2-x_1)`

We have the points (3, 8) and (1, 3).

Substitute:

`m=(3-8)/(1-3)=(-5)/(-2)=2.5`

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The point-slope formula:

`y-y_1=m(x-x_1)`

Substitute:

`y-8=2.5(x-3)`

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The slope-intercept form:

`y=mx+b`

Substitute the value of a slope:

`y=2.5x+b`

Substitute the coordinates of the point (1, 3) to the equation of line:

`3=2.5(1)+b\\3=2.5+b\qquad|-2.5\\b=0.5`

Final, we have:

`y=2.5x+0.5`