the longer side / the shorter side must be the same for rectangles to be similar.
For A: 105 / 80 = 1.32
For B: 120 / 90 = 1.33
For C: 100 / 75 = 1.47
So... only A and B are similar.
This can be determined by finding the x-intercept. In doing so, we let y=0 to find the value of x.
y= 2x^2 -x -3
[0 = 2x^2 -x-3]÷2
0 = x^2 -1/2 x - 3/2
Complete the squares:
1/16 + 3/2 = x^2 - 1/2x + 1/16
25/16 = (x -1/4)^2
sqrt (25/16) = x - 1/4
+/- 5/4 = x - 1/4
Thus,
x = 1/4 + 5/4 = 3/2
x = 1/4 - 5/4 = -1
Thus, the graph crosses at x = 3/2 and x = -1.
15.9687194227 units between the 2 points