CBSE Class 8 Mathematics Algebraic Expressions And Identities Worksheet Set B

Question. Find the degree of the polynomial 5x³ - 6x³y + 4y² - 8.
(A) 3
(B) 4
(C) 2
(D) 6
Answer : B

Question. What is the measure of the third side of a triangle given that its two sides are a² - 2a + 1 and 3a² - Sa + 3 and has a perimeter 6a² - 4a + 9?
(A) 2a² - 3a - 5
(B) 2a² + 3a - 5
(C) 2a² + 3a + 5
(D) 2a² - 3a + 5
Answer : C

Question. Two sides of a rectangle are (3p + 5q) units and (Sp- 7q) units. What is its area in sq. units?
(A) 15p² + 4pq - 35q²
(B) 15p² - 4pq + 35q²
(C) 15p² + 14pq + 35q²
(D) 15p² - 4pq - 35q²
Answer : A

Question. The difference of x⁴ + 2x² - 3x + 7 and another polynomial is x³ + x² + x - 1. What is the other polynomial ?
(A) x⁴ - x³ + x² - 4x + 8
(B) x³ + x² - 4x + 8
(C) x⁴ - x³ + x² + 4x - 8
(D) x⁴ - x³ - x² + 4x - 8
Answer : A

Question. Find the side of a square field of area

Answer : D

Question. Given that x - 1/x = 5 , find the value of x² + 1/x²
(A) - 27
(B) 23
(C) 27
(D) - 23
Answer : C

Question. Find the missing term in the following expression.
(3x/4 - 4y/3)² = 9x²/16 +....... + 16y²/9
(A) 2xy
(B) -2xy
(C) 12xy
(D) -12xy
Answer : B

Question. The sum of two expressions is x³ -x² + 3x- 2. If one of them is x² + 5x- 6, what is the other ?
(A) x³ - 2x² - 2x - 4
(B) x³ + 3x² - 2x + 4
(C) x³ - 2x² - 2x + 4
(D) -x³ - 2x² + 2x - 4
Answer : C

Question. If (3x - 4)(5x + 7) = 15x² - ax- 28, what is the value of 'a'?
(A) 1
(B) -1
(C) - 2
(D) 2
Answer : B

Question. Find the product of (x² + 3x + 5) and (x 2 -1).
(A) x⁴ + 3x³ - 4x² - 3x - 5
(B) x⁴ + 3x³ + 4x² - 3x - 5
(C) x⁴ + 3x³ + 4x² + 3x - 5
(D) x⁴ - 3x³ - 4x² + 3x - 5
Answer : B

Question. What is the difference obtained when x³ - xy² + 5x²y - y³ is subtracted from - y³ - 6x²y - xy² + x³ ?
(A) 2y³ - 8x²y + 3xy²- 2x³
(B) 2x³ - 2xy² - x 2y - 2y³
(C) - 11x 2y
(D) 11x²y
Answer : C

Question. If 3x- 7y = 10 and xy = - 1, find the value of 9x² + 49y²
(A) 58
(B) 142
(C) 1 04
(D) -104
Answer : A

Question. What is the va1ue of 7.83 x 7.83 - 1.17 x 1.17/6.66 ?
(A) 9
(B) 6.66
(C) 1.176
(D) -9
Answer : A

Question. What must be added to x³ + 3x - 8 to get 3x³ + x 2 + 6 ?
(A) 2x³ + x² - 3x + 14
(B) 2x² + x² + 14
(C) 2x³ + x² - 6x -14
(D) -2x³ - x² + 6x - 14
Answer : A

Question. If x² + 1/x² = 79, what is the value of X + 1/x ?
(A) 7
(B) 9
(C) J79
(D) -9
Answer : B

Question. Evaluate the expression 81p² + 16q² -72pq when P = 2/3 and q = 3/4.
(A) -16
(B) 9
(C) -9
(D) 16
Answer : B

Question. The area A, of a solid is given by the formula A = πr² + 2n rh + πrl. Find the value of A given that n = 3.142, r = 10, h = 3 and l = 4.
(A) 629
(B) 628.4
(C) 630
(D) 631
Answer : B

Question. If the perimeter of the figure given is 57 em, find the perimeter of the triangle in the figure.

(A) 30 cm
(B) 45 cm
(C) 39 cm
(D) 3 cm

Answer : B
 

Q1 The degree of the expression 2x-4xy2+5x2y3

Q2 The number of terms in a binomial is

Q3 What must be subtracted from 2x2-3x+4 to get x2 +2x-1?

Q4 The product of 3x2 and -5xy3 is

Q5 The product of (x+3) and (2x-1) is

Q6 The product of (x+y) (x-y) (x2+y2) is

Q7 What will be the remainder when 3x2-2x+1 is divided by x+5?

Q8 What will be the remainder when x6-3x2-10 is divided by x3-1?

Q9 What must be added to y3-y2-3y-2 to get y2-5y+6?

Q9 Find the value of <a> if (2x-5) (x+3)=2x2+x+a?

Q10 When (3y+1)(2y-3)=6y2+ay-3, what will be the value of (a)?

Q11 If x=3, y=2, then (x-y)(x2+xy+y2) is

Q12 Add (i) 3m2+8m-4 and 6m2-m+7 (ii) a2+2ab and -3ab-d2

Q13 Simplify (i) 4x-(-8y-3x) (ii)-(49-a2)-9a2

Q14 Subtract 72pq-30q2-15p2 from 30p2+40q2-12pq ?

Please click the below link to access CBSE Class 8 Algebraic Expressions and Identities Worksheet (1)