Answer:
486
Step-by-step explanation:
Hello!
To find the surface area of a cube we use the equation

S is the surface area
a is the side length
Put what we know into the equation

Solve
S = 6 * 81
S = 486
Hope this Helps!
2.77 × 10 ^ ( -3 ) is the answer
Answer:
Plates are 2.80 Dollars and cups are 1.40 dollars
Step-by-step explanation:
Cups = c
Plates = p
6p + 5c = 23.80 ==> multiply by 6 ==> 36p + 30c = 142.80
7p + 6c = 28.00 ==> multiply by 5 ==> 35p + 30c = 140.00
Now use algebra to have the 30c be on one side and the rest on the other:
36p + 30c = 142.80 | -36p
30c = 142.80 - 36p
35p + 30c = 140.00 | -35p
30c = 140.00 - 35p
Now set them equal to each other about the 30c:
142.80 - 36p = 140.00 - 35p
Use algebra to solve for p:
142.80 - 36p = 140.00 - 35p | +36p
142.80 = 140.00 + p | - 140
2.80 = p
Go back to one of the "30c" equations and plug in the value for p:
30c = 140 - 35p
30c = 140 - 35(2.80)
30c = 140 - 98
30c = 42 | /30
c = 42/30
c = 1.4
Answer:
Third option
O 100 cm
1m
Step-by-step explanation:

Area of rectangle is the multiplication between the sides.
The first rectangle:
A = (2x + 5) . (3x - 2)
A = 2x . 3x - 2 . 2x + 5 . 3x - 2 . 5
A = 6x² - 4x + 15x - 10
A = 6x² + 11x - 10
The second rectangle:
A = (5y + 5) . (2y - 3)
A = 5y . 2y - 3 . 5y + 5 . 2y - 3 . 5
A = 10y² - 15y + 10y - 15
A = 10y² - 5y - 15