Answer: 4°F
Step-by-step explanation:
83 and 89 are prime numbers between 80 and 90.
Area = 64π
Circumference = 2πr or πd
diameter = 16 (Diameter times π = 16π so this is obvious)
radius = diameter divided by 2 = 8
Area = πr², so π times 8² = π times 64 = 64π
for these you need to rearrange the equations and do substitutions.
#3 = if x+y=5 then you know x = 5-y
now substitute that equation for x in the 2nd one so x + 2y = 8 becomes
5-y + 2y = 8 2y - y becomes 1y which becomes y then subtract 5 from each side to get y =3
now replace y with 3 in the first equation x = 5-3 so x = 2
so (2,3) is the answer
same type of work for #4
2x-y=6 ,S0 y = 2X+6
so now you have 4x+2(2x+6)=-4
that becomes 4x +4x+12 = -4
8x+8 = 1, x =1
y = 2(1)-6 = -4
so answer is (1,-4)
Using exponential functions, the ending balances are given as follows:
1. $1,490.07.
2. $1,073.83.
3. $358.04.
<h3>What is an exponential function?</h3>
An increasing exponential function is modeled by:

In which:
- A(0) is the initial value.
- r is the growth rate, as a decimal.
Item a:
The parameters are:
A(0) = 939, r = 0.08, t = 6.
Hence the balance is:

Item b:
The parameters are:
A(0) = 823, r = 0.03, t = 9.
Hence the balance is:

Item c:
The parameters are:
A(0) = 269, r = 0.1, t = 3.
Hence the balance is:

More can be learned about exponential functions at brainly.com/question/25537936
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