Find the Equation Using Slope-Intercept Form (-2,-3) , m=9

$(- 2, - 3)$ , $m = 9$

Find the value of $b$ using the formula for the equation of a line.

Use the formula for the equation of a line to find $b$ .

$y = m x + b$

Substitute the value of $m$ into the equation.

$y = (9) \cdot x + b$

Substitute the value of $x$ into the equation.

$y = (9) \cdot (- 2) + b$

Substitute the value of $y$ into the equation.

$- 3 = (9) \cdot (- 2) + b$

Find the value of $b$ .

Rewrite the equation as $(9) \cdot (- 2) + b = - 3$ .

$(9) \cdot (- 2) + b = - 3$

Multiply $9$ by $- 2$ .

$- 18 + b = - 3$

Move all terms not containing $b$ to the right side of the equation.

Add $18$ to both sides of the equation.

$b = - 3 + 18$

Add $- 3$ and $18$ .

$b = 15$

Now that the values of $m$ (slope) and $b$ (y-intercept) are known, substitute them into $y = m x + b$ to find the equation of the line.

$y = 9 x + 15$