Quiz Quidelines
1. Read and understand the Question. 2. Pay attention to details. 3. There are for options per Question. 4. You only have one chance to choose the correct answer.
Quiz
1. Solve for x : ( x 2 - 4 ) ( x - 2 ) = 0
2. Solve for x : ( x - 1 ) ( x + 8 ) = 10
3. Solve for x : 4x 2 + 11x + 4 = 0
(Leave your answer correct to TWO decimal places IF NECESSARY)
4. Solve for x : - x 2 ≤ 4 - 5x
5. Solve for x : 6x < 3x 2
6. Solve for x and y if and
6. Solve for x and y if and
6. Solve for x and y if
and
7. Solve for x and y if and
7. Solve for x and y if and
7. Solve for x and y if
and
8. Solve for x and y if = 1 and
8. Solve for x and y if = 1 and
8. Solve for x and y if
= 1 and
9. Given: x =
Determine the value(s) of b for which x is a Real Number.
10. The roots of a quadratic equation are given by: x =
- 2 ±
13 – 2k
3
10. The roots of a quadratic equation are given by: x =
- 2 ±
13 – 2k
3
10. The roots of a quadratic equation are given by:
x =
- 2 ±
13 – 2k
3
For how many values of k > 0 will the roots be Rational ?
What does HTML stand for?
Quiz Results
Solutions
1. Solve for x : ( x 2 - 4 ) ( x - 2 ) = 0
Correct Answer
Option B
Detailed Solution
Solution Details
Given ( x 2 - 4 ) ( x - 2 ) = 0
• ( x 2 - 4 ) ( x - 2 ) = 0
• ( x 2 - 4 ) = 0 or ( x - 2 ) = 0
∴ x = ± 2 or x = 2
For more info please see
Algebra
2. Solve for x : ( x - 1 ) ( x + 8 ) = 10
Correct Answer
Option C
Detailed Solution
Solution Details
Given ( x - 1 ) ( x + 8 ) = 10
• ( x - 1 ) ( x + 8 ) = 10
• x 2 + 7x - 8 = 10
• x 2 + 7x - 18 = 0
• ( x + 9 ) ( x – 2 ) = 0
• ( x + 9 ) = 0 or ( x – 2 ) = 0
∴ x = – 9 or x = 2
For more info please see
Algebra
3. Solve for x : 4x 2 + 11x + 4 = 0
(Leave your answer correct to TWO decimal places IF NECESSARY)
Correct Answer
Option C
Detailed Solution
Solution Details
Given 4x 2 + 11x + 4 = 0
• 4x 2 + 11x + 4 = 0
• x =
– b ±
b 2 – 4ac
2a
The equation cannot be factorised so we use the quadratic formula
• x =
– 11 ±
( 11 ) 2 – 4 ( 4 ) ( 4 )
2 ( 4 )
=
– 11 ±
57
8
• x =
– 11 –
57
8
or x =
– 11 +
57
8
∴ x = – 0.43 or x = – 2.32
For more info please see
Algebra
Given 4x 2 + 11x + 4 = 0
• 4x 2 + 11x + 4 = 0
• x =
– b ±
b 2 – 4ac
2a
The equation cannot be factorised so we use the quadratic formula
• x =
– 11 ±
( 11 ) 2 – 4 ( 4 ) ( 4 )
2 ( 4 )
=
– 11 ±
57
8
• x =
– 11 –
57
8
or
x =
– 11 +
57
8
∴ x = – 0.43 or x = – 2.32
For more info please see
Algebra
4. Solve for x : - x 2 ≤ 4 - 5x
Correct Answer
Option A
Detailed Solution
Solution Details
Given - x 2 ≤ 4 - 5x
• - x 2 ≤ 4 - 5x
• x 2 - 5x + 4 ≥ 0
• ( x - 1 ) ( x – 4 ) ≥ 0
• x 2 - 5x + 4 = 0 at x = 1 and x = 4
+0-0+
||||
|14|
We have to find values of x where x 2 - 5x + 4 ≥ 0
∴ x ≤ 1 or x ≥ 4
For more info please see
Algebra
5. Solve for x : 6x < 3x 2
Correct Answer
Option A
Detailed Solution
Solution Details
Given 6x < 3x 2
• 6x < 3x 2
• 3x 2 - 6x > 0
• 3x ( x – 2 ) > 0
• 3x 2 - 6x = 0 at x = 0 and x = 2
+0-0+
||||
|02|
We have to find values of x where 3x 2 - 6x > 0
∴ x < 0 or x > 2
For more info please see
Algebra
6. Solve for x and y if and
6. Solve for x and y if and
6. Solve for x and y if
and
Correct Answer
Option C
Detailed Solution
Solution Details
Given and
• ................................... 2
• Substitute 1 into 2
∴
• Substitute the values of x into 1 to get the values of y
y = x + 2
For x = - 4
y = - 4 + 2 = - 2
For x = 2
y = 2 + 2 = 4
∴ ( x ; y ) = ( - 4 ; - 2 ) and ( x ; y ) = ( 2 ; 4 )
For more info please see
Algebra
Given and
• ................................... 2
• Substitute 1 into 2
∴
• Substitute the values of x into 1 to get the values of y
y = x + 2
For x = - 4
y = - 4 + 2 = - 2
For x = 2
y = 2 + 2 = 4
∴ ( x ; y ) = ( - 4 ; - 2 ) and
( x ; y ) = ( 2 ; 4 )
For more info please see
Algebra
7. Solve for x and y if and
7. Solve for x and y if and
7. Solve for x and y if
and
Correct Answer
Option A
Detailed Solution
Solution Details
Given and
• ................................... 2
• From 1 we have
y = 2x - 3 ................................... 3
• Substitute 3 into 2
∴
• Substitute the values of x into 3 to get the values of y
y = 2x - 3
For x = -
1
5
y = 2 ( -
1
5
) - 3 = -
17
5
For x = 2
y = 2 ( 2 ) - 3 = 1
∴ ( x ; y ) = ( -
1
5
; -
17
5
) and ( x ; y ) = ( 2 ; 1 )
For more info please see
Algebra
Given and
• ........................ 2
• From 1 we have
y = 2x - 3 ........................ 3
• Substitute 3 into 2
∴
• Substitute the values of x into 3 to get the values of y
y = 2x - 3
For x = -
1
5
y = 2 ( -
1
5
) - 3 = -
17
5
For x = 2
y = 2 ( 2 ) - 3 = 1
∴ ( x ; y ) = ( -
1
5
; -
17
5
) and
( x ; y ) = ( 2 ; 1 )
For more info please see
Algebra
8. Solve for x and y if
= 1 and
8. Solve for x and y if
= 1 and
8. Solve for x and y if
= 1 and
Correct Answer
Option A
Detailed Solution
Solution Details
Given and
• ................................... 2
• From 1 we have
y = 2x - 1 ................................... 3
• Substitute 3 into 2
∴
• Substitute the values of x into 3 to get the values of y
y = 2x - 1
For x = - 1
y = 2 ( - 1 ) - 1 = - 3
For x =
1
3
y = 2 (
1
3
) - 1 = -
1
3
∴ ( x ; y ) = (
1
3
; -
1
3
) and ( x ; y ) = ( - 1 ; - 3 )
For more info please see
Algebra
Given and
• ........................ 2
• From 1 we have
y = 2x - 1 ........................ 3
• Substitute 3 into 2
∴
• Substitute the values of x into 3 to get the values of y
y = 2x - 1
For x = - 1
y = 2 ( - 1 ) - 1 = - 3
For x =
1
3
y = 2 (
1
3
) - 1 = -
1
3
∴ ( x ; y ) = (
1
3
; -
1
3
) and
( x ; y ) = ( - 1 ; - 3 )
For more info please see
Algebra
9. Given: x =
Determine the value(s) of b for which x is a Real Number.
Correct Answer
Option C
Detailed Solution
Solution Details
Given x =
±
b 2 – 9
- 2
• x =
±
b 2 – 9
- 2
• b 2 – 9 ≥ 0
• ( b - 3 ) ( b + 3 ) ≥ 0
∴ b ≤ - 3 or b ≥ 3
For more info please see
Algebra
10. The roots of a quadratic equation are given by: x =
- 2 ±
13 – 2k
3
10. The roots of a quadratic equation are given by: x =
- 2 ±
13 – 2k
3
10. The roots of a quadratic equation are given by:
x =
- 2 ±
13 – 2k
3
For how many values of k > 0 will the roots be Rational ?
Correct Answer
Option C
Detailed Solution
Solution Details
Given x =
- 2 ±
13 – 2k
3
• x =
- 2 ±
13 – 2k
3
• The roots of a quadratic equation are Rational if Δ = 0, or if Δ is a Perfect Square
∴ 13 – 2k = 0
∴ k =
• And there are three numbers that are less than 13 which are Perfect Squares. They are 1, 4 and 9.
∴ 13 – 2k = 1 or 13 – 2k = 4 or 13 – 2k = 9
∴ k = 6 or
k =
or
k =
∴ The roots are Rational if k ∈ (
;
;
;
6 )
∴ There are 4 values k > 0 for which the roots are Rational
For more info please see
Algebra
Given x =
- 2 ±
13 – 2k
3
• x =
- 2 ±
13 – 2k
3
• The roots of a quadratic equation are Rational if Δ = 0, or if Δ is a Perfect Square
∴ 13 – 2k = 0
∴ k =
• And there are three numbers that are less than 13 which are Perfect Squares. They are 1, 4 and 9.
∴ 13 – 2k = 1 or 13 – 2k = 4 or 13 – 2k = 9
∴ k = 6 or
k =
or
k =
∴ The roots are Rational if
k ∈ (
;
;
;
6 )
∴ There are 4 values k > 0 for which the roots are Rational
For more info please see
Algebra