D. 32/47
You would subtract 1580 from 640 to get 940. You would then simplify 640/940 to get 32/47.
Since it is the midpoint we can say:
12x - 1 = 8x +11
All we have do to is get all the x's alone on one side
12x - 1 = 8x + 11
12x = 8x + 12 (add both sides by 1)
4x = 12 (subtract both sides by 8x)
x = 3 (divide both sides to get what x is)
I think 1,5 ? Might be very wrong but that’s my guess ♀️
H(t) = 0 for t = 7 and for t = -2.
It is reasonable for the time to be positive, 7 seconds.
(The offered answers all appear to be negative, so none are reasonable.)