Answer:
1300 middle school students.
Step-by-step explanation:
We can turn the words into this expression:
2000 x 65/100
And that expression simplifies to 1300, so 1300 students.
Answer:
Radius = 4.51
Step-by-step explanation:
Area of building is 
.
<u>Step-by-step explanation:</u>
Here we have , a figure in given below picture where we have to find volume of this office building , Let's find out:
If we look closely we see that it's basically cuboid with dimensions 50 m by 110 m by 70 m . But there's one small cuboid sliced off from this cuboid with dimensions 50 m by 10 m by (110-90) m i.e. 50 m by 10 m by 20 m .
Area of building = Area of larger cuboid - Area of smaller cuboid
Area of cuboid = 
⇒ Area of building = Area of larger cuboid - Area of smaller cuboid
⇒ 
⇒ 
⇒ 
Therefore, Area of building is .
The answer is 53
——————————-
Answer:
prove that:
Sin²A/Cos²A + Cos²A/Sin²A = 1/Cos²A Sin²A - 2
LHS = \frac{Sin^2A}{Cos^2A} + \frac{Cos^2A}{Sin^2A}
Cos
2
A
Sin
2
A
+
Sin
2
A
Cos
2
A
= \begin{lgathered}= \frac{Sin^4A + Cos^4A}{Cos^2A . Sin^2A}\\\\Using\: a^2 + b^2 = (a+b)^2 - 2ab\\\\a = Cos^2A \: \& \:b = Sin^2A\\\\= \frac{(Sin^2A + Cos^2A)^2 - 2Sin^2A Cos^2A}{Cos^2A Sin^2A} \\\\Sin^2A + Cos^2A = 1\\\\= \frac{1 -2Sin^2A Cos^2A}{Cos^2A Sin^2A}\end{lgathered}
=
Cos
2
A.Sin
2
A
Sin
4
A+Cos
4
A
Usinga
2
+b
2
=(a+b)
2
−2ab
a=Cos
2
A&b=Sin
2
A
=
Cos
2
ASin
2
A
(Sin
2
A+Cos
2
A)
2
−2Sin
2
ACos
2
A
Sin
2
A+Cos
2
A=1
=
Cos
2
ASin
2
A
1−2Sin
2
ACos
2
A
\begin{lgathered}= \frac{1}{Cos^2A Sin^2A} - 2\\\\= RHS\end{lgathered}
=
Cos
2
ASin
2
A
1
−2
=RHS
LHS=RHS
