B. 20x and .8x because they have the same variable
A because two negatives make a positive
Answer:
Step-by-step explanation:
The given function is

The graph of this function is a parabola that opens downwards
The line
intersects this parabola, when

The teammate can spike the ball after 0.25 seconds or 0.5 seconds.
The two solutions are reasonable. When the volleyball is accelerating into the air, it passes a height of 8 after 0.25 seconds.
When the ball is dropping after it attains maximum height, it attains another height of 8 after 0.5 seconds again.
E^2x -2e^x -8=0 => e<span>^(2x) -2e^x -8=0
Temporarily replace e^x with y.
Then (y)^2 - 2y - 8 = 0. Factors are (y-4) and (y+2).
Roots are y = 4 and y= -2.
Now remembering that we temporarily replaced e^x with y, we let
y=4 = e^x. We need to solve for x. Taking the natural log of both sides, we get:
ln 4 = x (answer)
We have to discard the other root (y= -2), because we cannot take the ln of a negative number.
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