Step-by-step explanation:
ten students.
4(10)+95=135
6(10)+75=135
4x+95=6x+75
-75+4x+95=6x+75-75
4x+20=6x
-4x+4x+20=6x-4x
20=2x
(20=2x)/2
x=10
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?
You would do 69sq×3.1416. that gives you 14,957.1576 round it to the nearest hundreth, 14,957.16
4d=56
d=14. Ad a result, Dorothy is 14 years old. Hope it help!
