MCQ on Linear Equations in One Variable for Class 8
Class 8 Maths Chapter 2 Linear Equations in One Variable MCQ
MCQ of Linear Equations in One Variable Class 8
I. Choose the correct answer.
Question 1.
Which of the following is not a linear equation ?
A) 2x + 35 = 5
B) 3x + y = 10
C) 3x2 + 2x – 6 = 0
D) All the above
Answer:
C) 3x2 + 2x – 6 = 0
Question 2.
Which of the following is a linear equation in one variable ?
A) x + y + z = 8
B) 2x – 6 = 0
C) 2x2 + 3x – 6 = 0
D) All the above
Answer:
B) 2x – 6 = 0
Question 3.
An equation will always have
A) RHS & LHS
B) = sign
C) Variables
D) All the above
Answer:
D) All the above
Question 4.
A linear equation always have __________ .
A) one solution
B) more than one solutions
C) no solution
D) at least two solutions
Answer:
A) one solution
Question 5.
Solution of x – 7 = 3 is __________ .
A) x = 7
B) x = 7 or 3
C) x = 9
D) none
Answer:
D) none
Question 6.
Variables in the equation x2 + xy + z2 – 3xyz = p + 9 are ________ .
A) x, y, z, 9
B) p, 9
C) x, y, z, p
D) x, y, z, p, 9
Answer:
C) x, y, z, p
Question 7.
Rama has 5 rupees additional to Lakshman. If the total are 12, then equation represents above information is ________ .
A) x + 5 = 12
B) x + 12 = 5
C) x = 12 + 5
D) 5x = 12
Answer:
A) x + 5 = 12
Question 8.
My age is 5 less than twice of your age, then my age can be represented by the equation is ________ ?
A) y = 2x + 5
B) y = 2x – 5
C) y = 2x2 + 5
D) none
Answer:
B) y = 2x – 5
Question 9.
Solution of 2x – 3 = x + 2 is ________ .
A) x = 2
B) x = 3
C) x = 4
D) x = 5
Answer:
D) x = 5
Question 10.
If the equation ax + b = c is true for a value of x = d then the solution of above equation is _________ .
A) d
B) c
C) a
D) b
Answer:
A) d
Question 11.
Solve 2x + 8 = 16.
A) x = 10
B) x = -12
C) x = 4
D) x = 5
Answer:
C) x = 4
Question 12.
If 2x – 1 = 14 – x, then 2x + 5 = ________ .
A) 10
B) 15
C) 20
D) 25
Answer:
B) 15
Question 13.
If 3x – 6 = – 15, then x + 5 = _________ .
A) 0
B) 2
C) 5
D) 4
Answer:
B) 2
Question 14.
ax + 6 = 18 and x – 2 = 2, then a = ________ .
A) 3
B) 4
C) 6
D) 8
Answer:
A) 3
Question 15.
If \(\frac{8 x-3}{2}\) = 3x, then x = _________ .
A) -1
B) 1.5
C) 2
D) 2.5
Answer:
B) 1.5
Question 16.
If my age is ‘x’ years, then \(\frac{x}{5}\) – 3 illustrates ________ .
A) 3 years more to 5th part of my age
B) 5 years less to 3rd part of my age
C) 3 years less than 5th part of my age
D) none
Answer:
C) 3 years less than 5th part of my age
Question 17.
If the money with me is 5 more than five times of you, then it can be expressed as
A) 5x – 5
B) 5x + 5
C) 55x – 5
D) \(\frac{x}{5}\) + 5
Answer:
B) 5x + 5
Question 18.
Which of the following is a linear equation with two variables ?
A) x + y
B) x + y = 5
C) x + y > 5
D) x + y < 5
Answer:
B) x + y = 5
Question 19.
Two numbers are in a ratio of 6 : 5 and they differ by 3. Then they are ________ .
A) 6, 5
B)18, 21
C) 18, 15
D) 15, 18
Answer:
C) 18, 15
Question 20.
Ratio of boys and girls is 5 : 7, and girls are 14 more than boys. Then total students are _________ .
A) 14
B) 48
C) 35
D) 84
Answer:
D) 84
Question 21.
Assertion (A) : ( \(\frac{x}{5}\) + \(\frac{x}{12}\) – 3 = 17 is a linear equation in one variable.
Reason (R) : Standard form of linear equation in one variable is ax + b = c, when a. b, c are constants and Y is variable.
A) ‘A’ is false but (R) is true.
B) Both (A, R) are true and ‘R’ is correct explanation of A.
C) ‘A’ is true but (R) is false.
D) Both (A, R) are true but ‘R’ is not correct explanation of A.
Answer:
B) Both (A, R) are true and ‘R’ is correct explanation of A.
Question 22.
Assertion (A): Solution for the equation 3x – 5 = 7 is 4.
Reason (R): Value of the variable which makes LHS and RHS are equal is called solution.
A) A is false but (R) is true.
B) Both (A, R) are true and ‘R’ is correct explanation of A.
C) A is true but (R) is false.
D) Both (A, R) are true but ‘R’ is not correct explanation of A.
Answer:
B) Both (A, R) are true and ‘R’ is correct explanation of A.
Question 23.
Assertion (A) : In a 2 digit number the tens digit is ‘x’ and units digit is ‘y’. Then its value is 10x + y.
Reason (R) : Consecutive integers are x + 1,x + 2,x + 3, where x is an integers
A) ‘A’ is false but (R) is true.
B) Both (A, R) are true and ’R’ is correct explanation of A.
C) ‘A’ is true but (R) is false.
D) Both (A, R) are true but ‘R’ is not correct explanation of A.
Answer:
D) Both (A, R) are true but ‘R’ is not correct explanation of A.
Question 24.
Which of the following is linear equation in one variable ?
A) x + y = 2
B) x2 + 3 = 2
C) x = y
D) x + 3 = 0
Answer:
D) x + 3 = 0
Question 25.
The solution of the equation \(\frac{3}{7}\) + x = \(\frac{17}{7}\) is _________
A) 3
B) 2
C) 1
D) 0
Answer:
B) 2
Question 26.
Which of the following equations is a linear equation in one variable ?
A) 2x + 3y = 10
B) 4a + 3b = 3b + 6
C) 2x = 3x + 4
D) 2x + 4z = 5
Answer:
C) 2x = 3x + 4
Question 27.
Twenty years from now, Arjun will become three times as old as he is now. Suitable equation for this is __________
A) 2x + x = 20
B) 3x = x + 20
C) 3x = 20
D) 3x + x = 20
Answer:
B) 3x = x + 20
Question 28.
Geetha, Kamini and Lokesh win Rs 2000 in a presentation competition. They share the prize money as follows :
• Geetha takes Rs y.
• Kamini gets Rs 300 less than Geetha’s share.
• Lokesh’s share is twice as much as Kamini
What is Kamini’s share ?
A) Rs. 250
B) Rs. 275
C) Rs. 425
D) Rs. 725
Answer:
C) Rs. 425
Question 29.
What is the solution of 3x – 5 = 9 ?
A) \(\frac{4}{3}\)
B) 2
C) \(\frac{14}{3}\)
D) 8
Answer:
C) \(\frac{14}{3}\)
Question 30.
Which of the following is a LINEAR equation ?
A) 3x + 2 = 8
B) 3x2 + 2x = 8
C) \(\frac{1}{x}\) + 2 = 8 x
D) \(\frac{3}{x}\) + 2x2 = 8 x
Answer:
A) 3x + 2 = 8
Question 31.
There are two consecutive odd integers. If three times of the first number is added to five times of the second number, the result is 50. What are the two numbers ?
A) 3 and 5
B) 5 and 6
C) 5 and 7
D) 6 and 8
Answer:
C) 5 and 7
Question 32.
If \(\frac{x}{4}\) = \(\frac{-7}{4}\) then x = ________
A) \(\frac{-7}{16}\)
B) -7
C) \(\frac{-16}{7}\)
D) -28
Answer:
B) -7
Question 33.
Which of the following is linear equation in one variable ?
A) x2 + 2 = 6
B) x + y = 3
C) 2x + 1 = 5
D) x2 = 9
Answer:
C) 2x + 1 = 5
Question 34.
x = 2 satisfies which of the following equations ?
A) x + 3 = 5 x
B) x – 3 = – 1
C) \(\frac{x}{2}\) = 1
D) All of the above
Answer:
D) All of the above
II. Fill in the blanks.
1. Variable and constant in the equation 3x + 5 = 8 are _________ .
Answer:
3, 5, 8
2. LHS and RHS of 2x – 3 = 18 are _________ .
Answer:
2x – 3, 18
3. Solution of 2x – 3 = 17 is _________ .
Answer:
10
4. If \(\frac{x}{5}\) + 3 = 8, then x – 1 = _________
Answer:
24
5. Sum of two numbers is 38 and the smaller is 12 less than the other. Then they are ________ and ________ .
Answer:
13, 25
6. Given 2(x + 2\(\frac{3}{4}\)) = 13, then x = _________ .
Answer:
3\(\frac{3}{4}\)
7. Sum of two consecutive integers is 25, then the linear equation which expresses the above is _________ .
Answer:
x + (x + 1) = 25
8. The standard form of linear equation in one variable is _________ .
Answer:
ax + b = c
9. On adding 15 to a certain num ber gives 35. The equational representation to above is _________ .
Answer:
x + 15 = 35
10. \(\frac{x}{6}\) = 7 verbal representation is _________ .
Answer:
Sixth part of a number is equal to 7
III. Matching the following.
Question 1.
| A | B |
| 1) \(\frac{x}{6}\) = 7 | a) 100x + 10(2x) 4 |
| 2) 2x – 3 = x + 2, then x = ________ | b) \(\frac{4}{5}\) |
| 3) Value of 100 rupees notes in (x) number and 10 rupees notes twice to above is _______ | c) 5 |
| 4) \(\frac{9 x}{15}\) = 7 – 6x, then 2x = ________ | d) \(\frac{35}{33}\) |
| 5) If 3p = 5p – \(\frac{8}{5}\) , then p = ________ | e) 42 |
Answer:
(1, e) (2, c) (3, a), (4, d) (5, b)
| A | B |
| 1) \(\frac{x}{6}\) = 7 | e) 42 |
| 2) 2x – 3 = x + 2, then x = ________ | c) 5 |
| 3) Value of 100 rupees notes in (x) number and 10 rupees notes twice to above is _______ | a) 100x + 10(2x) 4 |
| 4) \(\frac{9 x}{15}\) = 7 – 6x, then 2x = ________ | d) \(\frac{35}{33}\) |
| 5) If 3p = 5p – \(\frac{8}{5}\) , then p = ________ | b) \(\frac{4}{5}\) |
Question 2.
| A | B |
| 1) When ‘9’ is subtracted from twice a number gives 17, then the number is | a) \(\frac{2 x}{5}\) |
| 2) Twice of a number is divided by 5. | b) \(\frac{x}{5}\) + 5 |
| 3) 5 is added to 5th part of a number | c) 10x + y |
| 4) 2x – 7 = – 13 then x = ________ | d) 13 |
| 5) Value of two digit number (xy) is ________ | e) -3 |
Answer:
(1, d) (2, a), (3, b) (4, e), (5, c)
| A | B |
| 1) When ‘9’ is subtracted from twice a number gives 17, then the number is | d) 13 |
| 2) Twice of a number is divided by 5. | a) \(\frac{2 x}{5}\) |
| 3) 5 is added to 5th part of a number | b) \(\frac{x}{5}\) + 5 |
| 4) 2x – 7 = – 13 then x = ________ | e) -3 |
| 5) Value of two digit number (xy) is ________ | c) 10x + y |