(6 + 3) + 21 = 6 + (3 + 21)
It's an ASSOCIATIVE PROPERTY
(a + b) + c = a + (b + c)
C. −6, is the best option
#1 first we need to solve for slope which is y2-y1/x2-x1
plug in the coordinates and get 1-6/5-(-2) which makes our slope -5/7
then use the equation for point slope form which is:
y-y1=m(x-x1)
then plug in one of the coordinates, I'll use (-2,6), now we have
y-6=-5/7(x+2)
now to make this slope intercept, we just have to solve
y-6=-5/7x-10/7
y=-5/7x+4 4/7
repeat all these steps for 2 and 3
#2: slope = -13/5
plug it in to point slope and get: y+8=-13/5(x-3)
slope intercept:
y+8= -13/5x + 39/5
y= -13/5x -1/5
#3: slope = 3/4
point slope form: y-2=3/4(x-3)
slope intercept: y-2=3/4x-9/4 --> y=3/4x-1/4
