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Champ Jee
Subject: Maths
, asked on 27/3/18
Example 8.
In this question's solution, how triangle BCE similar to ACF? It's not given they are equilateral.
Answer
2
Charulatha
Subject: Maths
, asked on 27/3/18
8. In the given figure DE
∥
B
C
,
i
f
B
D
=
x
-
3
,
A
B
=
2
x
,
C
E
=
x
-
2
a
n
d
A
C
=
2
x
+
3
.
F
i
n
d
x
.
Answer
1
Himanshu Sharma
Subject: Maths
, asked on 26/3/18
Q. In trapezium ABCD, AB
∥
CD and DC = 2 AB. EF drawn parallel to AB cuts AD in F and BC in E such that
B
E
E
C
=
3
4
.
Diagonal DB intersects EF at G. Prove that 7 FE = 10 AB.
Answer
1
Akshit Gupta
Subject: Maths
, asked on 26/3/18
Solve this:
Q.8. In the given figure, if DE
∥
BC, find the ratio of ar (
△
ADE) and ar (DECB).
Answer
3
Anjali Srivastava
Subject: Maths
, asked on 26/3/18
Answer with explanation.
Q.45.
a
r
△
A
B
C
a
r
q
u
a
d
r
i
l
a
t
e
r
a
l
X
Y
C
B
=
_
_
_
_
_
_
_
_
_
_
_
,
i
f
X
Y
∥
B
C
Answer
2
Yash Behl
Subject: Maths
, asked on 26/3/18
Q. A hemispherical tank full of water is emptied by a pipe at the rate of
3
4
7
liters per second. How each time will it take to empty half the tank, if it is 3 m in diameter?
Q. In triangle ABC, if AD is the median, show that
A
B
2
+
A
C
2
=
2
A
D
2
+
B
D
2
Q. Prove that :
cos
e
c
θ
-
sin
θ
(
s
e
c
θ
-
cos
θ
)
=
1
tan
θ
+
c
o
t
θ
.
Answer
7
अर्कज ..
Subject: Maths
, asked on 26/3/18
Q.29. A container opens at the top and made up of metal sheet is in the form of a frustum of a cone of height 16 cm with diameters of its lower and upper ends are 16 cm and 40 cm respectively. Find the cost of metal sheet sued to make the container, if it costs Rs. 10 per 100
c
m
2
.
U
s
e
π
=
3
.
14
Answer
1
अर्कज ..
Subject: Maths
, asked on 26/3/18
Solve this:
Q.24. A thief away from a Police Station with a uniform speed 100 m/minutes. After one minute a policeman runs behind the thief to catch him. He goes at a speed of 100 m/minute in first minute and increases the speed 10 m/minute each succeeding minute. After how many minutes the Policeman catches the thief.
Now answer these questions:
(i) Which mathematical concept is being used to solve the above problem?
(ii) Which trait of personality of the policeman is showed?
Answer
1
अर्कज ..
Subject: Maths
, asked on 26/3/18
Q.19. An observer 1.5 m tall is 28.5 m away from a chimney. The angle of elevation of the top of the chimney from her eyes is
45
°
. What is the height of the chimney.
Answer
1
Khushi Jain
Subject: Maths
, asked on 25/3/18
Solve this:
Q27. If
a
≠
b
≠
0
, prove that the points (a, a
2
), (b, b
2
) (0, 0) will not be collinear.
Answer
1
Dipesh Kumar Karesia
Subject: Maths
, asked on 25/3/18
Q. ABC is an Isosceles triangle which AB = AC = 10 cm and BC = 12 cm. PQRS is a rectangle inside the isosceles triangle. If PQ = SR = y cm, PS = QR = 2x. then prove that x = 6 — 3y/4.
Answer
1
Ayan
Subject: Maths
, asked on 25/3/18
plz sir why sir in the last step they took triangles such as BCD and BAC cant we take the triangle in the last step as BDC and ABC i not getting in which manner we should take the triangles while whie solving the problem .plz tell
Answer
1
Champ Jee
Subject: Maths
, asked on 24/3/18
Q6.
If it comes for 4 marks, I will join my shortcut method!
I used a median theorem, which is itself mentioned in optional exercise as a question... Will I be awarded 4 marks if I use this shortcut method?
Answer
5
Champ Jee
Subject: Maths
, asked on 24/3/18
Is my proof for AAA similarity criterion correct?
Answer
1
Leena Sen
Subject: Maths
, asked on 24/3/18
AD is the median of triangle ABC, O is any point on AD. BO and CO produced meet AC and AB in E and F respectively. AD is produced to X such that OD=DX. Pdove that AO:AX=AF:AB
Answer
1
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What are you looking for?
In this question's solution, how triangle BCE similar to ACF? It's not given they are equilateral.
Q.8. In the given figure, if DE BC, find the ratio of ar (ADE) and ar (DECB).
Q.45.
Q. A hemispherical tank full of water is emptied by a pipe at the rate of liters per second. How each time will it take to empty half the tank, if it is 3 m in diameter?
Q. In triangle ABC, if AD is the median, show that
Q. Prove that :
Q.24. A thief away from a Police Station with a uniform speed 100 m/minutes. After one minute a policeman runs behind the thief to catch him. He goes at a speed of 100 m/minute in first minute and increases the speed 10 m/minute each succeeding minute. After how many minutes the Policeman catches the thief.
Now answer these questions:
(i) Which mathematical concept is being used to solve the above problem?
(ii) Which trait of personality of the policeman is showed?
Q27. If , prove that the points (a, a2), (b, b2) (0, 0) will not be collinear.
If it comes for 4 marks, I will join my shortcut method!
I used a median theorem, which is itself mentioned in optional exercise as a question... Will I be awarded 4 marks if I use this shortcut method?