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:
27 years
Step-by-step explanation:
Given that :
Adrian's age = 3
Father's age = 34
In how many years will Adrian be twice as young as his father?
Let the number of years = x
2(3 + x) = 34 + x
6 + 2x = 34 + x
2x - x = 34 - 6
x = 28
Answer:
Step-by-step explanation:
a) sum of angle on the straight line TRW is 180.
Given <TRS = 2x+10
<SRW = x-10
<TRS+<SRW = 180
2x+10+x-10 = 180
3x = 180
x = 180/3
x = 60°
<TRV = 180°-(2x+10)
Substitute x = 60° into the expression
<TRV = 180-(2(60)+10)
<TRV = 180-(120+10)
<TRV = 180-130
<TRV = 50°
2) From the diagram attached <MHJ= <LHK (oppositely directed angle)
Given
<MHJ= x+15
<LHK = 2x-20
Substitute the given data into the formula to get x
x+15= 2x-20
x-2x = -15-20
-x = -35
x = 35°
Next is to get the measure of <MHJ
<MHJ = x+15
<MHJ = 35+15
<MHJ = 50°
Yes and no, (4, 5) multiplied by 2 is (10, 8) but reversed. It depends on how you look at it because (10, 8) would be on the other side of the graph than (8, 10) which is the actually equivalent.