Find the Equation Using Slope-Intercept Form (1,-3) , m=-5/4

$(1, - 3)$ , $m = - \frac{5}{4}$

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.

$y = (- \frac{5}{4}) \cdot x + b$

Substitute the value of $x$ into the equation.

$y = (- \frac{5}{4}) \cdot (1) + b$

Substitute the value of $y$ into the equation.

$- 3 = (- \frac{5}{4}) \cdot (1) + b$

Find the value of $b$ .

Rewrite the equation as $- \frac{5}{4} \cdot 1 + b = - 3$ .

$- \frac{5}{4} \cdot 1 + b = - 3$

Multiply $- 1$ by $1$ .

$- \frac{5}{4} + b = - 3$

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

Add $\frac{5}{4}$ to both sides of the equation.

$b = - 3 + \frac{5}{4}$

To write $- 3$ as a fraction with a common denominator, multiply by $\frac{4}{4}$ .

$b = - 3 \cdot \frac{4}{4} + \frac{5}{4}$

Combine $- 3$ and $\frac{4}{4}$ .

$b = \frac{- 3 \cdot 4}{4} + \frac{5}{4}$

Combine the numerators over the common denominator.

$b = \frac{- 3 \cdot 4 + 5}{4}$

Simplify the numerator.

Multiply $- 3$ by $4$ .

$b = \frac{- 12 + 5}{4}$

Add $- 12$ and $5$ .

$b = \frac{- 7}{4}$

Move the negative in front of the fraction.

$b = - \frac{7}{4}$

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.

$y = - \frac{5}{4} x - \frac{7}{4}$

Step 3