Question

What is the equation of a line passing through (3,2) and having a y−intercept of 5?

A.y=x+5
B.y=x−5
C. y=−x+5
D. y=−x−5

Answer 1

C

Explanation:

the equation of a line in slope- intercept form is

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

calculate the slope m , using the slope formula

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

let (x₁, y₁ ) = (0, 5 ) , coordinates of y- intercept and (x₂, y₂ ) = (3, 2 )

substitute these values into the formula for m

m =
`(2-5)/(3-0)` =
`(-3)/(3)` = - 1

with y- intercept c = 5

y = - x + 5 ← equation of line