### Algebraic Expressions - Worksheets

CBSE Worksheet-1
CLASS -VII Mathematics (Algebraic Expressions
)

Choose correct option in questions 1 to 4.
1. Multiply 2a and 3a.
a. 6a2
b. 5a2
c. a2
d. 12a2
2. Get the algebraic expressions for subtraction of z from y.
a. y + z
b. y - z
c. y × z
d. $\frac{y}{z}$
3. Find the value of x + 4 for x = 2.
a. 2
b. 4
c. 6
d. 8
4. Find the product of (2x + 3y) (2x + 3y).
a. 5x2 + 9y2 + 12xy
b. 4x2 + 7y2 + 12xy
c. 4x2 + 9y2 + 13xy
d. 4x2 + 9y2 + 12xy
Fill in the blanks:
1. When terms have the same algebraic factor, they are called __________.
2. An expression which contains two unlike terms is called _______.
3. A _________ can take various values.
4. Find the product:$\left(\frac{2}{3}xyz\right)\left(\frac{3}{4}{x}^{2}{y}^{2}{z}^{2}\right)\left(\frac{4}{5}{x}^{3}{y}^{3}{z}^{3}\right)$ .
5. Simplify these expressions and find their values,if x= 3,a= - 1,b= - 2.
a. 3x- 5a - x+ 9b
b. 2b - 8x + 4x2 + 4a
6. Simplify combining like terms:
a. 3- 2ab - (ab) + 3ab a
b. 5x2- 5x2 + 3yx2 - 3y2 + x2 - y2 + 8xy2 - 3y2
7. What should be taken away from 3x2 - 4y2 + 5xy + 20 to obtain - x2 - y2 + 6xy + 20?
CBSE Worksheet-1
CLASS -VII Mathematics (Perimeter and Area)

1. a
2. b
3. c
4. d
Explanation: (2x + 3y) (2x + 3y) = 2x(2x + 3y) +3y(2x + 3y)
= 4x2 + 6xy + 6xy +9y2 = 4x2 + 9y2 + 12xy
5. like terms
6. binomial
7. variable
8. $\phantom{\rule{thickmathspace}{0ex}}\frac{2}{5}{x}^{6}{y}^{6}{z}^{6}$
9. a. -13
Explanation: when x = 3,a= - 1,= - 2.
3x- 5a -x2+ 9b = 3x3 - 5 x(-1) - (3)2 + 9 (-2)= 9 + 5 -9 -18 = -13
b. 4
Explanation: when x = 3,a= - 1,b = - 2.
2b - 8x+ 4x2+ 4a = 2(-2) - 8(3) + 4(3)2 + 4(-1) = -4 - 24 + 36 - 4 = 4
10. a. ab
Explanation: 3- 2ab - (ab) + 3ab a
= 3a - 2b - ab - a + b - ab + 3ab + b - a = a + ab

b. 8x2+ 8xy2 - 4x2 - 7y2
Explanation: 5x2- 5x2 + 3yx2 - 3y2 + x2 - y2 + 8xy2 - 3y2
= 8x2- 4x2 - 7y2 + 8xy2
11. 4x2 - 3y2 - xy
Explanation: 3x2 - 4y2 + 5xy + 20 - (- x2 - y2 + 6xy + 20)
= 3x2 - 4y2 + 5xy + 20 + x2 + y2 - 6xy - 20
= 4x2 - 3y2 -xy