Minus the 21 from the other side of the equation making it 7x=-21 then u divide the 7 from the x to the -21 resulting in x=-3
Answer:
it the first choice you ate three chocolate independently
Answer:
f(n)= 5 · 4

Step-by-step explanation:
You use the explicit formula for geometric sequence. The five is the firat term and is placed correctly. The 4 is the rate of change, because if you multiply 5 by 4 you get 20 and so on.