B, x=12 because 140-80=60, 60/5=12
9 thousands 3 hundreds 2 tens 6 ones
or
9326
Step-by-step explanation:
that is
sum(2^r) for r=1 to n, plus sum(1/2) for r=1 to n.
and that is
sum(2^r) + n/2 for r=1 to n.
2^r is a geometric sequence with 2 being the common ratio (every new term is created by multiplying the previous term by 2).
and since r is starting at 1, the first term a1 = 2.
the formula for the sum of a finite geometric sequence is
Sn = a1×(1 - r^n) / (1 - r)
with r being the common ratio .
so, in our case
Sn = 2×(1 - 2^n) / (1 - 2)
Sn = (2 - 2^(n+1)) / -1 = 2^(n+1) - 2
and so, in total we get
2^(n+1) - 2 + n/2 = 2^(n+1) + (n - 4)/2
<h3>Answer:</h3>
For your first answer it is because they are two different ways to solve the equation
<h3>Step-by-step explanation:</h3>
For Example!
<h2>Solution 1:</h2>
(x-4)² – 28 = 8The 8 is positive making it a different equation (this is like absolute value). (I am assuming you know the answer to the probelm)
<h2>Solution 2:</h2>
(x-4)² – 28 = -8
The 8 could be negative meaning that when you add the 28 to the right side it is -8+28 which will be a negative!
<h3>I hope this helps</h3><h2>IF IT DOES HELP PLEASE GIVE IT A BRAINLIEST!</h2>