Question

Write the equation of a line through points (5,5) and (1, 0) in point-slope form?

Answer 1

Explanation:

I’m assuming that the equation is to be written in slope intercept form (y=mx+b), so for this, you want to find the slope and y-intercept. To find the slope, use the equation in picture 1.

0 - 5 = -5

1 - 5 = -4

-5 / -4 = 1.25

So m, or the slope, is equal to 1.25.

To find the y-intercept, make a table like the second picture. Choose one of the ordered pairs as the given. I used 1,0.

0,?

1,0

Now find the change in x, which in this case, is 1. Then set up something like picture three.

1.25/1 = ?/1

?=1.25

Now backtrack to get:

0, -1.25

1, 0

Now we know what is y when x is 0, we know the y intercept and can make the equation:

y = 1.25x - 1.25