congratulations to Alexa and Rose
Answer:
C) 471
Step-by-step explanation:
Surface area for a cylinder formula:
SA = 2πrh + 2πr²
Given:
r = 5
h = 10
Work:
SA = 2πrh + 2πr²
SA = 2(3.14)(5)(10) + 2(3.14)(5²)
SA = 314 + 2(3.14)(25)
SA = 314 + 157
SA = 471
Let x = your number.
x^2 - 21 = 4x. Subtract 4x from both sides.
x^2 - 4x - 21 = 0. Factor.
(x - 7) (x + 3) = 0. Set each term to 0.
x + 3 = 0. Subtract 3 from both sides.
x = -3. This is the negative solution.
Set the other term equal to zero.
x - 7 = 0. Add 7 to each side.
x = 7. This is the positive solution.
Answer:
Step-by-step explanation:
-11/5+-3/4
(-11/5)*4+(-3/4)*5
(-44/20)+(-15/20)
-59/20
