How do you write the point slope form of an equation for a lint that passes through (-2, 4) with m=-3?

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Answer 1 · 2017-04-10T16:22:59

$y = - 3 x - 2$ $y=-3x-2$

Use the generl point-slope equatio of, $y = m x + b$ $y=mx+b$

Where $m =$ $m=$ slope and $b =$ $b=$ y-intercept

Given that $m = - 3$ $m=-3$ the equation of the line now looks like $y = - 3 x + b$ $y=-3x+b$

Given $P (- 2, 4)$ $P(-2,4)$ , subsitute the $x$ $x$ and $y$ $y$ coordinates into the equation and solve for $b$ $b$ ,

$4 = - 3 \cdot - 2 + b$ $4=-3*-2+b$
$4 = 6 + b$ $4=6+b$
$b = - 2$ $b=-2$

Therefore the equation of the line with a slope of $- 3$ $-3$ that passes through the point $(- 2, 4)$ $(-2,4)$ is,

$y = - 3 x - 2$ $y=-3x-2$

graph{-3x-2 [-10, 10, -5, 5]}