Use the formula for the surface area of a right cone:

Where 'r' is the radius and 's' is the slant height, plug in what we know(use 3.14 to approximate for pi):

Multiply and simplify exponent:

Multiply:

Add, round to the nearest whole number:
Plug in x = 12 and y = -5 into the given equation:-
3(12) - 3(-5) = 36 + 15 = 51 Not 21
So (12,-5) is not a solution.
Answer:
A standard deck of cards consists of 52 cards. The colors are usually black for the spades and clubs and red for the hearts and diamonds.
Step-by-step explanation:
The price should be $36.75
The answer is a=7 because you have to do 7-6 which equals to 2 which a=7 is the right answer