The awenser of the problem is A
x(t) = 20t
y(t) = 40t - 5t^2
Since we are only interested in comparing the two at time t = 5 seconds, we plug in 5 everywhere we see the variable t and then compare x and y
x(5) = 20(5) becomes x(5) = 100
y(5) = 40(5) - 5(5)^2 becomes y(5) = 200 - 125 and then y(5) = 75
The ratio of y to x can be expressed as: y/x, so we can say the ratio is equal to 75/100 or 0.75
Answer: 0.75
It is answer choice A because you have to take the the GCF of each number which is 2x. Then if you were to divide the numbers by 2x you would put those numbers in the brackets.
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because
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and
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and