Question

Which equation describes the line through the points (4,-3) and (5,0)

Answer 1

y = 3x - 15

Explanation:

The equation of a line in slope- intercept form is

y = mx + c ( m is the slope and c the y- intercept )

Calculate m using the slope formula

m =
`(y_(2)-y_(1) )/(x_(2)-x_(1) )`

with (x₁, y₁ ) = (4, - 3) and (x₂, y₂ ) = (5, 0)

m =
`(0+3)/(5-4)` = 3 , thus

y = 3x + c ← is the partial equation

To find c substitute either of the 2 points into the partial equation

Using (5, 0 ), then

0 = 15 + c ⇒ c = 0 - 15 = - 15

y = 3x - 15 ← equation of line