Question

write an equation in slope-intercept form of the line that passes through the points (1,2) and (-2,-1)

Answer 1

y=3/4x+5/4

Explanation:

equation to use: y1-y2/x2-x1 so you get -3/-4 so your slope is 3/4 and you plug that into one of your point equations im going to use the first one so 2=3/4(1) +b so you are going to get 5/4 for b so your equation is y=3/4x + 5/4

Let me know if this helped!

Answer 2

An equation in slope-intercept form of the line that passes through the points (1,2) and (-2,-1) will be:

• y = x+1

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)

• (-2, -1)

Finding the slope between (1,2) and (-2,-1)

`\mathrm{Slope}=(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(-2,\:-1\right)`

`m=(-1-2)/(-2-1)`

`m=1`

substituting m = 1 and (1, 2) in the slope-intercept form of the line equation to determine the y-intercept

y = mx+b

2 = 1(1) + b

2 = 1+b

b = 2-1

b = 1

substituting m = 1 and b = 1 in the slope-intercept form of the line equation

y = mx+b

y = 1(x) + 1

y = x+1

Therefore, an equation in slope-intercept form of the line that passes through the points (1,2) and (-2,-1) will be:

• y = x+1