I suggest reading them over and over again to remember them. I know it sounds annoying, but trust me, it'll pay off.
Answer:
no solutions
Step-by-step explanation:
10x+2y=42
5x+y=20
Multiply the second equation by -2 to use elimination
-2(5x+y)=20*-2
-10x -2y = -40
Add this to the first equation
10x+2y=42
-10x -2y = -40
--------------------------
0 = 2
This is never true. This means there are no solutions
H(t) = 0 for t = 7 and for t = -2.
It is reasonable for the time to be positive, 7 seconds.
(The offered answers all appear to be negative, so none are reasonable.)
Volume is Length x width x height divided by 3. You have the length and the width. which equals 24. (6x4). The volume that is present is 72... the last thing you do in the equation is divide by three so multiply 72 by 3 and get 216. This is the LxWxH. Like I said before you have the L and the W, which is 24. You would divide 24 from 216. The Height is 9cm.
