Not easy:
- 4 < x^4 + 4x^2 ---> 0 < x^4+4x^2+4 = (x^2+2)^2, so it is always positive. Always satisfied. Curious ...
Now the other one:
x^4+4x^2<21 --> x^4+4x^2-21 < 0 --> (x^2+2)^2 - 25 < 0
(x^2+2)^2<25 ->>> x^2+2 < 5 ---> x^2 <3,
So -sqrt(3)<x<sqrt(3) is the answer! Brainliest?
Answer:
(d)0.6
Step-by-step explanation:
(a)Frequency Distribution

(b)The relative frequency distribution.

(c)The cumulative frequency distribution.

(d)The proportion of customers needing an oil change who wait 9 minutes or less.
Proportion of customers needing an oil change who wait 9 minutes or less.

21% were absent, if you divide 146 by 680 and multiply by 100, then round to the nearest whole number, you get 21
Since 3 is greater than -3, hence (-1, 3) lie in the solution set. Option C is correct
In order to determine the points that lie in the solution set of the inequality y > 3x +10, we will substitute the x-coordinate and see if <u>y is greater than the result.</u>
<u />
For the coordinate point (1, 10)
y > 3(1) +10
y > 13
Since 10 is not greater than 13, hence (1,10) does not lie in the solution set.
For the coordinate point (4, 20)
y > 3(4) +10
y > 22
Since 20 is not greater than 22, hence (4,20) does not lie in the solution set.
For the coordinate point (-1, 3)
y > 3(-1) +10
y > -7
Since 3 is greater than -3, hence (-1, 3) lie in the solution set.
Learn more on inequality here: brainly.com/question/24372553
8 would be the length of each piece of wire I think.