Algebraic Expressions(7th Grade > Mathematics ) Questions and answers for exam Preparation

7th Grade > Mathematics

ALGEBRAIC EXPRESSIONS MCQs

Total Questions : 116 | Page 2 of 12 pages

Question 11. The algebraic expression "x” does not contain any constant term.

True
False

Discuss Question

Answer: Option A. -> True
:
A
In the expression "x”, the variable is x and it does not have any constant term.
For example, in the expression 5 + 10y, the constant term is 5.
Hence, the statement is correct.

Question 12.

25 x^{2} + 5 + 15

is a binomial.

True
False

Discuss Question

Answer: Option B. -> False
:
B
A polynomial with two unlike terms is called a binomial and the one with three unlike terms is called a trinomial.
Hence,

25 x^{2} + 5 + 15

is a trinomial.

Question 13. The given expression '2x²+3y+5z²+10p+6y+7x^2', on simplification gives:

9x2+9y+5z2+10p
11x2+2y+10z2+10p
9x2+12y+5z2+10p
19x2+10y+5z2+10p

Discuss Question

Answer: Option A. -> 9x2+9y+5z2+10p
:
A
Given expression is
2x²+3y+5z² +10p+6y+7x²
Group the like terms:
= (2x²+7x²) + (3y+6y) + 10p + 5z²
Solve groups:
=x²(2+7)+y(3+6)+5z²+10p
=9x²+9y+5z²+10p

Question 14. The coefficient of x in '2x +5y' is __

Discuss Question

:
Coefficient is defined as anumber or symbol multiplied to a variable or an unknown quantity in an algebraic term.The coefficient of x in '2x + 5y' is 2.

Question 15. The coefficient of term

x^{5}

in the expression

x^{3} - x^{5}

is
___

Discuss Question

:
Coefficient is defined as anumber or symbol multiplied to a variable or an unknown quantity in an algebraic term.
The coefficient of the term

x^{5}

in expression

x^{3} - x^{5}

is -1,

- x^{5}

- 1 \times (x^{5})

∴

The coefficient of

x^{5}

is equal to -1.

Question 16. Find

(0.4 p - 0.5 q)^{2}

. If p = 5 and q = 4, evaluate the value of the expression. [3 MARKS]

Discuss Question

:
Steps: 1 Mark
Final expression: 1 Mark
Value: 1 Mark

(0.4 p - 0.5 q)^{2}

= (0.4 p - 0.5 q) \times (0.4 p - 0.5 q)

= (0.4 p) \times (0.4 p) - (0.4 p \times 0.5 q + 0.4 p \times 0.5 q) + (0.5 q) \times (0.5 q)

= 0.16 p^{2} - 0.40 p q + 0.25 q^{2}

Given that
p = 5 and q = 4
on substituting the values we get,

= 0.16 \times 5^{2} - 0.40 \times 5 \times 4 + 0.25 \times 4^{2}

= 4 - 8 + 4

= 0

Question 17. Subtract the sum of

(a + b + c)

and

(2 a - b + 2 c)

from

3 a - b + 3 c

. Name the type of expression formed. [3 MARKS]

Discuss Question

:
Answer: 1 Mark
Steps: 1 Mark
Type: 1 Mark
According to question,

(3 a - b + 3 c) - [(a + b + c) + (2 a - b + 2 c)]

= (3 a - b + 3 c) - [(a + b + c + 2 a - b + 2 c)]

= (3 a - b + 3 c) - (3 a + 3 c)

= (3 a - b + 3 c - 3 a - 3 c)

= - b

The given expression contains only

- b

, So it is a monomial.

Question 18. Is the statement given below correct? Explain.
"In the expression x + 4y + 4, the coefficient of x is 1, y is 4 and of 4 is 1". [2 MARKS]

Discuss Question

:
Answer: 1 Mark
Reason: 1 Mark
The statement is incorrect.
Acoefficient is defined as anumber or symbol multiplied to a variable or an unknown quantity in an algebraic term.
It is only defined for the terms containing variable and notfor constants.
In the expression, 4 is a constant and therefore cannot have a coefficient.
Hence, the statement is incorrect.

Question 19. From the sum of

4 + 3 x a n d 5 - 4 x + 2 x^{2}

,
subtract the sum of

3 x^{2} - 5 x a n d - x^{2} + 2 x + 5

. [4 MARKS]

Discuss Question

:
Forming the equation: 1 Mark
Steps: 2 Marks
Answer: 1 Mark
While adding or subtracting algebraic expressions we need to be aware that we can add/subtract only like terms.
Like terms have the same algebraic factors.
According to question,