Answer:
Step-by-step explanation:
Let 
Subbing in:
a = 9, b = -2, c = -7
The product of a and c is the aboslute value of -63, so a*c = 63. We need 2 factors of 63 that will add to give us -2. The factors of 63 are {1, 63}, (3, 21}, {7, 9}. It looks like the combination of -9 and +7 will work because -9 + 7 = -2. Plug in accordingly:
Group together in groups of 2:
Now factor out what's common within each set of parenthesis:
We know this combination "works" because the terms inside the parenthesis are identical. We can now factor those out and what's left goes together in another set of parenthesis:
Remember that 
so we sub back in and continue to factor. This was originally a fourth degree polynomial; that means we have 4 solutions.
The first two solutions are found withing the first set of parenthesis and the second two are found in other set of parenthesis. Factoring 
gives us that x = 1 and -1. The other set is a bit more tricky. If
then
and
You cannot take the square root of a negative number without allowing for the imaginary component, i, so we do that:
±
which will simplify down to
±
Those are the 4 solutions to the quartic equation.
Answer:
the mean and standard error of the mean are 200 and 2 respectively.
Step-by-step explanation:
Given that ;
the sample size n = 81
population mean μ = 200
standard deviation of the infinite population σ = 18
A population is the whole set of values, or individuals you are interested in, from an experimental study.
The value of population characteristics such as the Population mean (μ), standard deviation (σ) are said to be known as the population distribution.
From the given information above;
The sample size is large and hence based on the central limit theorem the mean of all the means is same as the population mean 200.
i.e
= 200
∴ The mean = 200
and the standard error of the mean can be determined via the relation:
Therefore ; the mean and standard error of the mean are 200 and 2 respectively.
3 because I said so and it is correct
Answer:
Step-by-step explanation:
AR⊥RS (tangent line is ⊥ to radius of the circle)
BS ⊥ RS (tangent line is ⊥ to radius of the circle.)
∴ AR and BS ⊥ to same line RS.
Hence either AR and BS are in same line or parallel.
But they are radii of different circles.
∴ AR ║BS
Answer:1072.3
Step by step:
use the hemisphere formula which is 2/3*pie*r^3
substitute 8 centimeters into the equation.
