Question

Write an equation in slope intercept form for the line that passes through (-1, -2) and (3, 4)

Answer 1

Answer:

The slope-intercept form of the line equation  is:

• $y=\:\frac{3}{2}x\:-\frac{1}{2}$

Step-by-step explanation:

The slope-intercept form of the line equation

y = mx+b

where

• m is the slope

• b is the y-intercept

Given the points

• (-1, -2)

• (3, 4)

Determining the slope between (-1, -2) and (3, 4)

$\mathrm{Slope}=\frac{y_2-y_1}{x_2-x_1}$

$\left(x_1,\:y_1\right)=\left(-1,\:-2\right),\:\left(x_2,\:y_2\right)=\left(3,\:4\right)$

$m=\frac{4-\left(-2\right)}{3-\left(-1\right)}$

$m=\frac{3}{2}$

Thus, the slope of the line is:

m = 3/2

substituting m = 3/2 and the point (3, 4) in the slope-intercept form of the line equation

y = mx+b

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

switch sides

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

$\frac{9}{2}+b=4$

subtract 9/2 from both sides

$\frac{9}{2}+b-\frac{9}{2}=4-\frac{9}{2}$

$b=-\frac{1}{2}$

now substituting m = 3/2 and b = -1/2 in the slope-intercept form of the line equation

$y = mx+b$

$y=\:\frac{3}{2}x\:+\:\left(-\frac{1}{2}\right)$

$y=\:\frac{3}{2}x\:-\frac{1}{2}$

Therefore, the slope-intercept form of the line equation  is:

• $y=\:\frac{3}{2}x\:-\frac{1}{2}$