Question

y = m x + b for a trend line that passes through the points (2, 18) and (–3, 8). Which value should he use as b in his equation

Answer 1

b = 14

Explanation:

the equation of a line in slope- intercept form is

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

calculate m using the slope formula

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

with (x₁, y₁ ) = (2, 18 ) and (x₂, y₂ ) = (- 3, 8 )

m =
`(8-18)/(-3-2)` =
`(-10)/(-5)` = 2 , then

y = 2x + b

to find b substitute either of the 2 points into the equation

using (2, 18 )

18 = 4 + b ⇒ b = 18 - 4 = 14