Question

Can someone please help me with this problem? An explanation would be great, but it can be short. Thank you!!

Answer 1

We are given two points: (4, -8) and (8, 5)

General equation of a line: y = mx + c

First find m (the gradient). There is a formula for this: (change in y)/(change in x) = gradient

(5 - -8) / (8 - 4) = (13) / (4) = 3.25 = m

y = 3.25x + c

Now we need to find c (the y-intercept; the value of y when x=0).

Substitute in any one of the coordinates - let's use (8, 5)

(5) = 3.25(8) + c

(5) = 26 + c

c = -21

The equation of the line: y = 3.25x - 21

I think that this answer is correct - sorry if it seems rushed.

Hope this answer helps :)