Same as all the other ones like this.
Since the two figures are similar . . .
-- The ratio of of their volumes is R³ .
-- The ratio of their surface areas is R² .
-- The ratio of their dimensions is R .
So R³ is 729 / 2744 .
Take the cube root of that and you'll have R .
Then square R and you'll have the ratio of their surface areas.
Solve for x over the real numbers:
-x^2 - 12 = -87
Add 12 to both sides:
-x^2 = -75
Multiply both sides by -1:
x^2 = 75
Take the square root of both sides:
Answer: x = 5 sqrt(3) or x = -5 sqrt(3) both Answers are correct
1) 2a = 9b ⇒ 2:9
2) a + b = 3b ⇒ a = 2b ⇒ 1:2
Answers: 2:9 and 1:2
C. Multiply $ 5 by 3, multiply $ 3 by 4, then multiply $ 13 by 3....then add the products together