Find the Equation Using Slope-Intercept Form (-1,-4) , m=3

$(- 1, - 4)$ , $m = 3$

Step 1

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.

$y = (3) \cdot x + b$

Substitute the value of $x$ into the equation.

$y = (3) \cdot (- 1) + b$

Substitute the value of $y$ into the equation.

$- 4 = (3) \cdot (- 1) + b$

Find the value of $b$ .

Rewrite the equation as $(3) \cdot (- 1) + b = - 4$ .

$(3) \cdot (- 1) + b = - 4$

Multiply $3$ by $- 1$ .

$- 3 + b = - 4$

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

Add $3$ to both sides of the equation.

$b = - 4 + 3$

Add $- 4$ and $3$ .

$b = - 1$

Step 2

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.

$y = 3 x - 1$

Step 3