Answer:
9+0.6+0.08
Step-by-step explanation:
199 is the answer because the equation you use is an=a1+d(n-1). Where an (the n is actually supposed to be smaller than the a) is the nth term (a40), a1 (1 smaller than a) is the first term (4), d is the difference (5), and n is the number of the term you're looking for (40)
5x^2= 2205
Divide both sides by 5
x^2=441
Find the square root of both sides
x= 21