Answer:
Volume: 41.643
Surface area: 119.04 (nearest tenth... I don't know...sorry)
Step-by-step explanation:
I didn't know if you need volume or surface area so you got both!
In order to find the area, you multiply the width (7), height (6) and length (12). But the problem states that the height has changed from 6 to 6 minus3, which would be 3. So you multiply 3, 7, and 12.
Answer:
22.5%
Step-by-step explanation:
The total number of students in percentage terms is 100%
Students that chose others = 100% - 40% - 37.5% = 22.5%
Answer:
x = 25/3; y = -5/3
Step-by-step explanation:
You did well so far by multiplying both sides of the first equation by 2.
Now notice that you have -2y in the new first equation and 2y in the second equation. -2y and 2y add to 0.
Now add the equations to eliminate y.
2x - 2y = 20
(+) 4x + 2y = 30
-------------------------
6x = 50
6x/6 = 50/6
x = 50/6 = 25/3
2x - 2y = 20
2(25/3) - 2y = 20
50/3 - 2y = 60/3
-2y = 60/3 - 50/3
-2y = 10/3
-2y/2 = (10/3)/(-2)
y = -5/3
Solution: x = 25/3; y = -5/3