Answer:
A = 78.5 cm²
Step-by-step explanation:
Area = π · radius²
if diameter is 10 then radius is 5
A = 5²·π
A = 25 × 3.14
A = 78.5 cm²
Answer:
see below
Step-by-step explanation:
The formula for the sum of an infinite geometric series with first term a1 and common ratio r (where |r| < 1) is ...
sum = a1/(1 -r)
Applying this to the given series, we get ...
a. sum = 5/(1 -3/4) = 5/(1/4) = 20
b. sum = d/(1 -1/t) = d/((t-1)/t) = dt/(t-1)
_____
The derivation of the above formula is in most texts on sequences and series. In general, you write an expression for the difference of the sum (S) and the product r·S. You find all terms of the series cancel except the first and last, and the last goes to zero in the limit, because r^∞ → 0 for |r| < 1. Hence you get ...
S -rS = a1
S = a1/(1 -r)
Answer:
12
Step-by-step explanation:
The answer is <span>2(–4y + 13) – 3y = –29
Step 1: Express </span><span>x from the second equation
Step 2: Substitute x into the first equation:
The system of equations is:
</span><span>2x – 3y = –29
x + 4y = 13
Step 1:
</span>The second equation is: x + 4y = 13
Rearrange it to get x: x = - 4y + 13
Step 2:
The first equation is: 2x – 3y = –29
The second equation is: x = - 4y + 13
Substitute x from the second equation into the first one:
2(-4y + 13) - 3y = -29
Therefore, the second choice is correct.
First, it is to be understood that logarithms allow a person to subject a number as an exponent of a base. As an example of ways in which logarithm is used to aid us in difficult calculations is when we calculate for the pH of a substance which has a formula of,
pH = -log[H+]