X=4 is the answer to this question
If f(x) = (3x + 7)²
then f(1) = (3(1) + 7)²
= 10²
⇒ f(1) = 100 [OPTION E]
Answer: 18
Step-by-step explanation:
Evaluate 7 r − 15 /s
Given that r = 3 and s = 5
7r - 15/s
Substitute 3 for r and 5 for s in the above expression
7(3) - 15/5
= 21 - 3
= 18
That would be 7 because 7x2=14 and 14-9=5
The ball's velocity will be represented by the derivative of its distance function:

Now find the times

for which this is equal to 30, i.e. solve

This has two solutions,

, but only one is positive and falls in the interval
![[0,3]](https://tex.z-dn.net/?f=%5B0%2C3%5D)
. So the velocity reaches 30 cm/s when

.