Question

Write the equation of the line that passes through the points (1, 7) and (5, 15) using function notation.

Answer 1

use the formula for a line through two points

`y - y_(1) = (y_(2) - y_(1))/(x_(2) - x_(1)) * (x - x_(1))`

plug in the given points:

`y - 7 = (15 - 7)/(5 - 1) * (x - 1)`

`y = (8)/(4) * (x - 1) + 7`

`y = 2 * (x - 1) + 7 \\ y = 2x - 2 + 7 \\ y = 2x + 5`