we are given
x^2-4x-5
we can use formula
x^2-(a+b)x+ab=(x-a)(x-b)
so, we have
a+b=4
ab=-5
now, we can solve for a and b
and we get
a=5, b=-1
now, we can plug it in formula
x^2-4x-5=(x-5)(x+1) ............Answer
From the information we have, we know that each book costs 1.20 dollars. So we shall say this price is at 100% .
Now we need to form an equation to get the percentage when the books are sold at 0.80 dollars.
100% = 1.20
x = 0. 80
Where x is the new percentage when the sale is at 0.80 dollars.
We cross multiply the equation:
1.20 *x = 0.80 * 100
1.2x = 80
x = 80/1.2
x = 66.7%
Round off 66.7 to the nearest tenth we get 67%
The notebooks are sold at 67% (of the original cost).
Answer:
47.5
Step-by-step explanation:
33+62=95
95/2=47.5
100% is whole, so 100 minus 57% equals 43% so 43% of 13 to 18 year olds are not influenced by celeberties.
Answer: This is a biased sample.
Step-by-step explanation:
A biased sample is when there is some kind of "selection" in your sampling process, where in order to avoid this we should have the most random selection that we can make
Here, the sample is "the first 15 students who arrive at a band class"
Here is obviously a bias, because you could think that these students may be more "dedicated" students than the ones that will arrive later to the class, and we also have the fact that all the students in our sample are in the same class, so there is another bias.
Then we can conclude that this is a biased sample.