Answer:
Choice A: [tex]y=-3x+4[/tex]
Step-by-step explanation:
For this we have to find the slope and the y-intercept.
Finding slope:
For slope we can use this formula [tex]m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex].
[tex]m=\frac{7--2}{2--1}[/tex]
There, now we solve it.
[tex]m=\frac{7--2}{-1-2}=\frac{9}{-3}=-3[/tex]
Slope is -3.
Finding the y-intercept:
We will plug in an ordered pair and the slope to this formula
I'll be using the ordered pair (-1,7).
[tex]y-y_1=m(x-x_1)\\y-7=-3[x-(-1)]\\y-7=-3x-3\\y=-3x+4[/tex]
So the y-intercept is 4.
And we already wrote the equation.
