# How do you write an equation in point slope form that passes through (-2,-4),m=3/4?

May 31, 2015

Equation of the line:$y = 3 \frac{x}{4} + b$

Find b by writing that this line passes at point (-2, -4)

$- 4 = \frac{3 \left(- 2\right)}{4} + b \to b = - 4 + \frac{3}{2} = - \frac{5}{2}$

y = 3x/4 - 5/2

May 31, 2015

The point-slope equation is $y + 4 = \frac{3}{4} \left(x + 2\right)$

The general equation for point-slope form is $y - {y}_{1} = m \left(x - {x}_{1}\right)$ .

Given/Known:

Slope = $\frac{3}{4}$

Point = $\left(- 2 , - 4\right)$

${x}_{1} = - 2$
${y}_{1} = - 4$

Substitute the given/known values into the point-slope equation.

$y - {y}_{1} = m \left(x - {x}_{1}\right)$ =

$y - \left(- 4\right) = \frac{3}{4} \left(x - \left(- 2\right)\right)$ =

$y + 4 = \frac{3}{4} \left(x + 2\right)$