Answer:
The three collinear poitns are D, A, and E.
Step-by-step explanation:
Collinear points are points that all reside on the same line. Since we are looking for 3 seperate points we need a line with 3 points. There are only 2 lines on the picture and only one has three lines getting you your answer.
You can do C(6,2) which gives

which is
15!
Answer:
see bottom
Step-by-step explanation:
divide through by 4
x2 - 2x - 3 = 0
x2 - 3x + x - 3 = 0
(x2 - 3x) + (x - 3) = 0
x(x - 3) + 1(x - 3) = 0
(x + 1) (x - 3) = 0
x + 1 = 0 and x - 3 = 0
x = -1 and x = 3