Question

help please! Darren is finding the equation in the form 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? a) –34 b) –19 c) 2 d) 14

Answer 1

Answer:  d) 14

Step-by-step explanation:

Equation of a line passing through (a,b) and (c,d):

$(y-b)=\dfrac{d-b}{c-a}(x-a)$

Equation of a line passing through (2, 18) and (–3, 8):

$(y-18)=\dfrac{8-18}{-3-2}(x-2)\\\\\Rightarrow\ (y-18)=\dfrac{-10}{-5}(x-2)\\\\\Rightarrow\ (y-18)=2(x-2)\\\\\Rightarrow\ y-18=2x-4\\\\\Rightarrow\ y=2x-4+18\\\\\Rightarrow\ y=2x+14$

Comparing resulting equation $y=2x+14$ to $y = m x + b$, we get value of b= 14.

Hence, correct option is d) 14