Answer:
2x^2 - x - 15 = 0.
Step-by-step explanation:
In factor form this is
(x + 5/2)(x - 3) = 0
x^2 + 5/2x - 3x - 15/2 = 0
x^2 - 1/2x - 15/2 = 0
Multiply through by 2:
She ran the last 100 meters in 2:15 -1:25 = 0:50, so her average speed was
... (100 m)/(50 s) = 2.0 m/s
