The third choice, 4x²+18x+0.25=0, is correct.
The frame will have the same thickness on both sides of the mirror. Therefore we add 5+x+x to get the total length, and we have 4+x+x to get the total width.
The area is found by multiplying the total width and total length:
A=(5+x+x)(4+x+x)
A=(5+2x)(4+2x)
Multiplying the binomials, we have:
A=5*4+5*2x+2x*4+2x*2x
A=20+10x+8x+4x²
A=20+18x+4x²
We know that the area is 19.75:
19.75=20+18x+4x²
We need quadratics set equal to 0, so subtract 19.75 from each side:
19.75-19.75 = 20+18x+4x²-19.75
0=0.25+18x+4x²
In standard form, it will be:
4x²+18x+0.25=0
The answer to the question is A.) 42
Answer:
The interval from the sample of size 400 will be approximately <u>One -half as wide</u> as the interval from the sample of size 100
Step-by-step explanation:
From the question we are told the confidence level is 95% , hence the level of significance is
=>
Generally from the normal distribution table the critical value of
is
Generally the 95% confidence interval is dependent on the value of the margin of error at a constant sample mean or sample proportion
Generally the margin of error is mathematically represented as
Here assume that
is constant so

=> 
=> 
So let
and 
=> 
=> 
=> 
So From this we see that the confidence interval for a sample size of 400 will be half that with a sample size of 100
A random variable is UNIFORMLY DISTRIBUTED whenever the probability is proportional to the interval's length.
Step-by-step explanation:
The unanimous Declaration of the thirteen united States of America, When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature