Answer:
SA = 2400 cm²
Step-by-step explanation:
SA of a cube = S² x 6 (the number of its faces)
SA = 20² x 6
SA = 400 x 6
SA = 2400 cm²
Dear Ajtocute, let's have x=9 Multiply 7 by 9 to get 63. Then, you divide 63 by 7 to get back to 9. You just cancel out the multiplication with division.
X = 20 degrees
Y = 30
This is acute triangle so all the sides and angles are the same. Subtract 16 from 46 and you receive 30 for y. For the corresponding angle, subtract 80 from 180. Then add 60 to that and subtract that from 180 for x.


When

, you're left with

When

or

, you're left with

Adding the two equations together gives

, or

. Subtracting them gives

,

.
Now, you have



By just examining the leading and lagging (first and last) terms that would be obtained by expanding the right side, and matching these with the terms on the left side, you would see that

and

. These alone tell you that you must have

and

.
So the partial fraction decomposition is
24 * 5 = 120
120 + 6 = 126 - total cost - meals and service
6/126 *100% = 4,76%
service charge was 4,76% of total costs.