First, you combine like terms. I would start by circling the term and the sign in front of it. (A term is a piece separated by an addition/subtraction sign.) You can only combine terms with the same variable. 4.8a-2.1a-6.3b+7b is the same as your equation, just rearranged. Then, subtract (4.8a-2.1a) which is 2.7a. Add (-6.3b to 7b) The answer is 0.7b. If you have any questions, you can message me!
Answer: 78.5 units^2
Step-by-step explanation:
The area of the circle is equal to pi*radius^2.
The diameter is double the radius, which means the radius is 10/2 = 5.
Therefore, the area is pi*5^2 = 25pi.
We use 3.14 for pi and we get 25*3.14 = 78.5 units^2