Answer:
50
Step-by-step explanation:
1/2 *H(l1+l2)
1/2*5(7cm+13cm)
1/2*5*20
1/2*100
50
Answer:
About 1.85 seconds and 13.15 seconds.
Step-by-step explanation:
The height (in feet) of the rocket <em>t</em> seconds after launch is given by the equation:

And we want to determine how many seconds after launch will be rocket be 390 feet above the ground.
Thus, let <em>h</em> = 390 and solve for <em>t: </em>
<em />
<em />
Isolate:

Simplify:

We can use the quadratic formula:

In this case, <em>a</em> = 8, <em>b</em> = -120, and <em>c</em> = 195. Hence:

Evaluate:

Simplify:

Thus, our two solutions are:

Hence, the rocket will be 390 feet above the ground after about 1.85 seconds and again after about 13.15 seconds.
(a) : y = 8 because 2x4 = 8
(b) : x = 9 because 9x4= 36
Sorry, the given solution is not valid, and unfortunately external links are not allowed, so it will be deleted.
I do not think that it is possible to visit every cell without revisiting any to go from one corner to the opposite one.