Question

Find the midpoint of the line y = 3x + 9 on the interval 1 < x < 9.
(x, y) = ?

Answer 1

(5, 24)

Explanation:

In order to find the midpoint of a line, you need two sets of coordinates. The formula to find the midpoint of a line is
`((x1+x2)/(2) ,(y1+y2)/(2) )`, where
`x1` is the x-coordinate of one of the coordinates and
`x2` is the x-coordinate of the second coordinate (and so on for
`y1` and
`y2`).

In this question, we're not given the two sets of coordinates to find the midpoint from. But we are told there is an interval 1 < x < 9, so first we substitute x=1 into the equation of the line:
`y=3`×
`1+9` = 3 + 9 = 12. So one of the coordinates is (1, 12). Doing the same with x=9, will give us y = 24.

Now if we use the formula I've written above, we should get (5, 24).