Answer:
Step-by-step explanation:
90°
The height that a ball reaches at a certain time t is given by the equation,
h = 2 - 15t + 5t²
We are asked to compute for the values of t that would allow the ball to reach a height of 7 meters.
Substitute the 7 to the equation,
7 = 2 - 15t + 5t²
Transposing,
5t² - 15t - 7 + 2 = 0
Simplifying,
5t² - 15t - 5 = 0
Divide the equation by 5,
t² - 3t - 1 = 0
The values of t can be calculated through the quadratic formula,
t = (-b +/- sqrt(b² - 4ac))/2a
Substituting,
t = (3 +/-sqrt (9 - 4(-1)) / 2(1)
t = 3.3 or t = -0.30
Since, we cannot have t as a negative number hence, our final answer is:
<em> t = 3.3 s</em>
Answer:
9x
Step-by-step explanation:
let's say that x is the number we don't know
the product means multiplication
9*x=9x
so the answer is 9x
Answer:
A)
Step-by-step explanation:
I did the test and got it correct please mark brainliest. I know it is correct.
