Page 1
Page No – 9.11
Solve each of the following equations and also check your results in
each case:
1.
( ???? +?? )
?? = 3x – 10
Solution:
( 2x+5)
3
= 3x – 10
Let us simplify,
( 2x+5)
3
– 3x = – 10
By taking LCM
( 2x + 5 – 9x)
3
= -10
( -7x+5)
3
= -10
By using cross-multiplication we get,
-7x + 5 = -30
-7x = -30 – 5
-7x = -35
x =
-35
-7
= 5
Let us verify the given equation now,
( 2x+5)
3
= 3x – 10
Page 2
Page No – 9.11
Solve each of the following equations and also check your results in
each case:
1.
( ???? +?? )
?? = 3x – 10
Solution:
( 2x+5)
3
= 3x – 10
Let us simplify,
( 2x+5)
3
– 3x = – 10
By taking LCM
( 2x + 5 – 9x)
3
= -10
( -7x+5)
3
= -10
By using cross-multiplication we get,
-7x + 5 = -30
-7x = -30 – 5
-7x = -35
x =
-35
-7
= 5
Let us verify the given equation now,
( 2x+5)
3
= 3x – 10
By substituting the value of ‘x’ we get,
( 2×5+5)
3
= 3(5) – 10
( 10+5)
3
= 15 – 10
15
3
= 5
5 = 5
Hence, the given equation is verified
2.
( ?? -?? )
?? =
( ?? -?? )
??
Solution:
( a-8)
3
=
( a-3)
2
By using cross-multiplication we get,
(a-8)2 = (a-3)3
2a – 16 = 3a – 9
2a – 3a = -9 + 16
-a = 7
a = -7
Let us verify the given equation now,
( a-8)
3
=
( a-3)
2
By substituting the value of ‘a’ we get,
( -7 – 8)
3
=
( -7 – 3)
2
Page 3
Page No – 9.11
Solve each of the following equations and also check your results in
each case:
1.
( ???? +?? )
?? = 3x – 10
Solution:
( 2x+5)
3
= 3x – 10
Let us simplify,
( 2x+5)
3
– 3x = – 10
By taking LCM
( 2x + 5 – 9x)
3
= -10
( -7x+5)
3
= -10
By using cross-multiplication we get,
-7x + 5 = -30
-7x = -30 – 5
-7x = -35
x =
-35
-7
= 5
Let us verify the given equation now,
( 2x+5)
3
= 3x – 10
By substituting the value of ‘x’ we get,
( 2×5+5)
3
= 3(5) – 10
( 10+5)
3
= 15 – 10
15
3
= 5
5 = 5
Hence, the given equation is verified
2.
( ?? -?? )
?? =
( ?? -?? )
??
Solution:
( a-8)
3
=
( a-3)
2
By using cross-multiplication we get,
(a-8)2 = (a-3)3
2a – 16 = 3a – 9
2a – 3a = -9 + 16
-a = 7
a = -7
Let us verify the given equation now,
( a-8)
3
=
( a-3)
2
By substituting the value of ‘a’ we get,
( -7 – 8)
3
=
( -7 – 3)
2
-15
3
=
-10
2
-5 = -5
Hence, the given equation is verified
3.
( ???? + ?? )
?? =
( ???? – ?? )
????
Solution:
( 7y+2)
5
=
( 6y – 5)
11
By using cross-multiplication we get,
(7y + 2)11 = (6y – 5)5
77y + 22 = 30y – 25
77y – 30y = -25 – 22
47y = -47
y =
-47
47
y = -1
Let us verify the given equation now,
( 7y+2)
5
=
( 6y – 5)
11
By substituting the value of ‘y’ we get,
( 7( -1) + 2)
5
=
( 6( -1) – 5)
11
( -7+2)
5
=
( -6 – 5)
11
-
5
5
= -
11
11
Page 4
Page No – 9.11
Solve each of the following equations and also check your results in
each case:
1.
( ???? +?? )
?? = 3x – 10
Solution:
( 2x+5)
3
= 3x – 10
Let us simplify,
( 2x+5)
3
– 3x = – 10
By taking LCM
( 2x + 5 – 9x)
3
= -10
( -7x+5)
3
= -10
By using cross-multiplication we get,
-7x + 5 = -30
-7x = -30 – 5
-7x = -35
x =
-35
-7
= 5
Let us verify the given equation now,
( 2x+5)
3
= 3x – 10
By substituting the value of ‘x’ we get,
( 2×5+5)
3
= 3(5) – 10
( 10+5)
3
= 15 – 10
15
3
= 5
5 = 5
Hence, the given equation is verified
2.
( ?? -?? )
?? =
( ?? -?? )
??
Solution:
( a-8)
3
=
( a-3)
2
By using cross-multiplication we get,
(a-8)2 = (a-3)3
2a – 16 = 3a – 9
2a – 3a = -9 + 16
-a = 7
a = -7
Let us verify the given equation now,
( a-8)
3
=
( a-3)
2
By substituting the value of ‘a’ we get,
( -7 – 8)
3
=
( -7 – 3)
2
-15
3
=
-10
2
-5 = -5
Hence, the given equation is verified
3.
( ???? + ?? )
?? =
( ???? – ?? )
????
Solution:
( 7y+2)
5
=
( 6y – 5)
11
By using cross-multiplication we get,
(7y + 2)11 = (6y – 5)5
77y + 22 = 30y – 25
77y – 30y = -25 – 22
47y = -47
y =
-47
47
y = -1
Let us verify the given equation now,
( 7y+2)
5
=
( 6y – 5)
11
By substituting the value of ‘y’ we get,
( 7( -1) + 2)
5
=
( 6( -1) – 5)
11
( -7+2)
5
=
( -6 – 5)
11
-
5
5
= -
11
11
-1 = -1
Hence, the given equation is verified
4. x – 2x + 2 –
???? ?? x + 5 = 3 –
?? ?? x
Solution:
x – 2x + 2 –
16
3
x + 5 = 3 –
7
2
x
Let us rearrange the equation
x – 2x –
16x
3
+
7x
2
= 3 – 2 – 5
By taking LCM for 2 and 3 which is 6
( 6x – 12x – 32x + 21x)
6
= -4
-
17x
6
= -4
By cross-multiplying
-17x = -4 × 6
-17x = -24
x =
-24
-17
x =
24
17
Let us verify the given equation now,
x – 2x + 2 –
16
3
x + 5 = 3 –
7
2
x
By substituting the value of ‘x’ we get,
24
17
- 2 (
24
17
) + 2 - (
16
3
)(
24
17
) + 5 = 3 - (
7
2
)(
24
17
)
Page 5
Page No – 9.11
Solve each of the following equations and also check your results in
each case:
1.
( ???? +?? )
?? = 3x – 10
Solution:
( 2x+5)
3
= 3x – 10
Let us simplify,
( 2x+5)
3
– 3x = – 10
By taking LCM
( 2x + 5 – 9x)
3
= -10
( -7x+5)
3
= -10
By using cross-multiplication we get,
-7x + 5 = -30
-7x = -30 – 5
-7x = -35
x =
-35
-7
= 5
Let us verify the given equation now,
( 2x+5)
3
= 3x – 10
By substituting the value of ‘x’ we get,
( 2×5+5)
3
= 3(5) – 10
( 10+5)
3
= 15 – 10
15
3
= 5
5 = 5
Hence, the given equation is verified
2.
( ?? -?? )
?? =
( ?? -?? )
??
Solution:
( a-8)
3
=
( a-3)
2
By using cross-multiplication we get,
(a-8)2 = (a-3)3
2a – 16 = 3a – 9
2a – 3a = -9 + 16
-a = 7
a = -7
Let us verify the given equation now,
( a-8)
3
=
( a-3)
2
By substituting the value of ‘a’ we get,
( -7 – 8)
3
=
( -7 – 3)
2
-15
3
=
-10
2
-5 = -5
Hence, the given equation is verified
3.
( ???? + ?? )
?? =
( ???? – ?? )
????
Solution:
( 7y+2)
5
=
( 6y – 5)
11
By using cross-multiplication we get,
(7y + 2)11 = (6y – 5)5
77y + 22 = 30y – 25
77y – 30y = -25 – 22
47y = -47
y =
-47
47
y = -1
Let us verify the given equation now,
( 7y+2)
5
=
( 6y – 5)
11
By substituting the value of ‘y’ we get,
( 7( -1) + 2)
5
=
( 6( -1) – 5)
11
( -7+2)
5
=
( -6 – 5)
11
-
5
5
= -
11
11
-1 = -1
Hence, the given equation is verified
4. x – 2x + 2 –
???? ?? x + 5 = 3 –
?? ?? x
Solution:
x – 2x + 2 –
16
3
x + 5 = 3 –
7
2
x
Let us rearrange the equation
x – 2x –
16x
3
+
7x
2
= 3 – 2 – 5
By taking LCM for 2 and 3 which is 6
( 6x – 12x – 32x + 21x)
6
= -4
-
17x
6
= -4
By cross-multiplying
-17x = -4 × 6
-17x = -24
x =
-24
-17
x =
24
17
Let us verify the given equation now,
x – 2x + 2 –
16
3
x + 5 = 3 –
7
2
x
By substituting the value of ‘x’ we get,
24
17
- 2 (
24
17
) + 2 - (
16
3
)(
24
17
) + 5 = 3 - (
7
2
)(
24
17
)
24
17
-
48
17
+ 2 –
384
51
+ 5 = 3 -
168
34
By taking 51 and 34 as the LCM we get,
( 72 – 144 + 102 – 384 + 255)
51
=
( 102 – 168)
34
-
99
51
= -
66
34
-
33
17
= -
33
17
Hence, the given equation is verified
5.
?? ?? ?? + ???? - ?? = ???? +
?? ??
Solution:
1
2x
+ 7x - 6 = 7x +
1
4
Let us rearrange the equation
1
2x
+ 7x - 7x =
1
4
+ 6 (by taking LCM)
1
2
x =
( 1+ 24)
4
1
2
x =
25
4
By cross-multiplying
4x = 25 × 2
4x = 50
x =
50
4
x =
25
2
Let us verify the given equation now,
Read More