Answer:
At 3.44 seconds, the penny is at a height of 300 meters above the ground.
Step-by-step explanation:
Basically, we have to solve an equation here:

Hence,



Hence, at 3.44 seconds, the penny is at a height of 300 meters above the ground.
Hope this helped!
If you graph this, your first point will be at (0,5), as the ramp is at the warehouse door but 5 feet up. The second point is (10,0) as it is touching the ground but it's 10 feet away from the warehouse.
To find slope, you do (y2-y1)/(x2-x1).
When substituting in the variables, you get (0-5)/(10-0), which is -5/10, which is simplified to -1/2. Of course, that is when the warehouse is Quadrant II. If you look at it from another point of view, the slope will be positive so your answer is A) 1/2.
If this was unclear feel free to comment :)
3a+b+c
The perimeter is two times one side (to account for the opposite) and two times the adjacent side. So if the sides would be x and y, the perimeter would be 2*x + 2*y.
So, knowing that the sum is 16a+8b-6c, if we subtract the given side 5a+3b-4c from this, what remains is two times the "other" side:
16a+8b-6c - 2*(5a+3b-4c) =
16a+8b-6c -10a-6b+8c =
6a+2b+2c
half of that is
(6a+2b+2c)/2 = 3a+b+c
(12^2 + 5) x 2
There you go. I wasn't sure if I was supposed to write an equation or...
= 298