the median of her 20 students is 82.5
Answer: D. Effects of UV rays on eyesight
Step-by-step explanation:
The whole point of this study is to find the effects of people either with wearing or not wearing sunglasses for 10 weeks and being exposed to UV rays.
Answer:
x=√2, x=-√2, x= 3 and x=-3
Step-by-step explanation:
We need to solve the equation x^4 - 11x^2+18=0
We can replace x^4 = u^2 and x^2 = u
So, the equation will become
u^2 -11u+18 = 0
Factorizing the above equation:
u^2 -9u-2u+18 =0
u(u-9)-2(u-9)=0
(u-2)(u-9)=0
u=2, u=9
As, u = x^2, Putting back the value:
x^2 =2 , x^2 =9
taking square roots:
√x^2 =√2 ,√x^2=√9
x=±√2 , x = ±3
so, x=√2, x=-√2, x= 3 and x=-3
7.
assuming you mean SURFACE area
look at shape
fold it out or whateveryo yo like
we see that the faces are
4 triangles
4 rectangles in midddle
4 more triangles on other side
calculate areas
area of triangle=1/2bh
area of rectangle=bh
leftmost side
h=1.8
b=2
4*1/2*2*1.8=7.2 cm^2
middle recangles
base=3
height=2
aera=3*2=6
multply by 4 snce 4 recangles
6*4=24 cm^2
other triangles
b=2
h=2.71
total area=4*1/2*2*2.71=10.84cm^2
add them up
7.2cm^2+24cm^2+10.84cm^2=42.04cm^2
8. interesting question, not enought time to answer for me and partially too copmplex
