I think it's c because if its proportional it should also be linear and c is the only linear equation
Since x is the number of seconds it took the rock to hit the water, x is the value that we are looking for. When the rock hits the water, it's height is 0, therefore, f(x) = 0. So, we can set the expression on the right equal to 0, and solve for 0. Let's do just that:

We can divide by -16, nothing will happen because 0 divided by anything is 0:

To factor any trinomial in standard form (given below), we must find two numbers that add to "b" and multiply to "c":

So, for this specific question, let's find two numbers that add to -8 and multiply to 9. These are clearly 9 and -1. We can write it in this way now:

Both answers would be valid, but there can't be negative time, so your answer is
"It takes 9 seconds for the rock to reach the water."
Answer:
7.5 seconds.
Step-by-step explanation:
Substitute the distace 220m in the given equation:
d = 19t + t^2
200 = 19t + t^2
t^2 + 19t - 200 = 0
t = [-19 +/- sqrt(19^2 - 4*1*-200)] / 2
t = -19 +/- sqrt(1161) / 2
t = ( -19 +/- 34.07) / 2
t = 7.535 seconds
Answer:
75th term
Step-by-step explanation:
hope it is well understood
Answer:
7
Step-by-step explanation:
An equilateral triangle has a semiperimeter of 6 meters.
Heron’s formula: Area = StartRoot s (s minus a) (s minus b) (s minus c) EndRoot
An equilateral triangle has a semiperimeter of 6 meters. What is the area of the triangle? Round to the nearest square meter.
2 square meters
7 square meters
20 square meters
78 square meters