If the area for a circle is

, you can write it in terms of its diameter like this:
Answer:
x=1
Step-by-step explanation:
To solve this question we will have to open the bracket first
So let's solve
3(x-5)=18
Open the bracket
3x-15=18
Add 15 to both sides
3x=3
Make x the subject of formula by dividing both sides by 3
x=1
So the final answer is 1
Answer:
20:a , a=48
Step-by-step explanation:
5*4=20, 12*4 = 48
Simple mathematics, you multiple 5 by 4 to get 20, do the same thing to 12.