Question

Write an equation in standard form of the line passing through the points (12, 3) and (-3, 8).

Answer 1

Answer:

x + 3y = 21

Step-by-step explanation:

$(x_{1},y_{1})=(12,3) \\\\(x_{2},y_{2})=(-3,8)\\\\Slope= \dfrac{y_{2}-y_{1}}{x_{2}-x_{1}}\\\\= \dfrac{8-3}{-3-12}= \dfrac{5}{-15}\\\\= \dfrac{-1}{3}$

Equation of the line: y =mx+ b

$y = \dfrac{-1}{3}x+b\\\\\\Plugin \ x = 12 \ and \ y=3 \ in \ the \ above \ equation\\\\3= \dfrac{-1}{3}*12+b\\\\3= -4+b\\\\3+4 = b\\\\b = 7\\\\\\\y= \dfrac{-1}{3}x+7$

Multiply the equation by 3

3y = -x + 21

x + 3y = 21