Geometry:(
*image shown above*

Step-by-step explanation:

so we use the equation y2-y1=m(x2-x1)

let's say (-3,1) is point 1 and (-5,8) is point 2

we plug in what we know

8-1=m(-5-(-3))

subtracting a negative is the same as adding so -5 - (-3) = -2

7=-2m

divide both sides by -2

-7/2=m

-3.5=m

so slope intercept form is y=mx+b

we know the slope (m) but we still need the "b" which is the y-intercept.

so you pick whichever point you want (I'm going to chose point 1 but it doesn't matter) and plug it in

1=-3.5(-3)+b

1=10.5+b

-9.5=b

so the equation would be y=-3.5x-9.5

the volume is the product of the area of the base, 3x(3x+4), and the height, 3x-1

step-by-step explanation: