Answer:
Statement 1 and 2
Step-by-step explanation:
If you take t^2 - 16t + 55 and find some of its graphical values, you will get:
Turning point: (8,-9)
Roots: (5,0) and (11,0)
When this graph is plotted and you imagine the x axis to be time (as stated in the question), each of the roots (x - intercept) must be when the swimmer goes under and when they come back up.
This means that the swimmer dived under the water at 5 seconds and came back up at 9, making the first 2 statements correct.
Now the fourth statement is ruled out.
The fifth statement is not plausible as the graph would have to have more than 2 roots for the swimmer to enter the water twice.
That leaves the third statement. If you imagine the depth of the swimmer to be the y axis of our imaginary graph, and we know that the y axis of the turning point is -9, that means that the swimmer's deepest dive was 9 feet under the water, ruling out the third statement too.
Hope this helps :D
Answer:
Step-by-step explanation:
The first problem, all you need to do is combine like terms then isolate the n:
4n-2n=4
~subtract 2n from 4n (2n)
2n=4
~then divide both sides of the equation by 2 to isolate the n
n=4
The second problem follows the same steps of combining like terms and isolating the variable. Here, you'll have to combine 2 like terms:
-12=2+5v+2v
~first combine the variables which is just 5v+2v which is 7v
-12=2+7v
~then subtract 2 from both sides to isolate the 7v
-14=7v
~then divide both sides by 7 to isolate the v and get your answer
-2=v
Hope that helped!