Question

Mike correctly found the slope and y-intercept of the line passing through the points (–5, –2) and (3, 14) as follows.

m = StartFraction 14 minus (negative 2) Over 3 minus (negative 5) EndFraction = StartFraction 16 Over 8 EndFraction = 2. y = 2 x + b. Negative 2 = 2 (negative 5) + b. Negative 2 + 10 = negative 10 + b + 10. b = 8.


What is the equation of the line in slope-intercept form?
y = 2 x minus 8
y = 2 x + 8
y = 8 x minus 2
y = 8 x + 2

Answer 1

y = 2x + 8

Explanation: slope m = (14 - (-2)) / (3 - (-5)) = 16/8 = 2. Using (-5,-2): -2 = 2(-5) + b ⇒ -2 = -10 + b ⇒ b = 8.