# Free Algebraic Expressions 03 Practice Test - 7th grade

25x2+5+15  is a binomial.

A.

True

B.

False

#### SOLUTION

Solution : B

A polynomial with two unlike terms is called a binomial and the one with three unlike terms is called a trinomial.
Hence, 25x2+5+15
is a trinomial.

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

A.

True

B.

False

#### SOLUTION

Solution : 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.

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

#### SOLUTION

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

On subtracting (x+a) from (4x+3a), the result obtained is_____.

A.

3x+2a

B.

9x+6a

C.

11x+2a

D.

3x+7a

#### SOLUTION

Solution : A

Arrange the polynomials with like terms one below the other. Change the sign of each term to be subtracted and then combine the like terms.

4x + 3a    x +  a()    ()         3x + 2a

(4x+3a)(x+a)=3x+2a

Find the value of the expression 5ab for a = 3, b = 2.

A.

30

B.

40

C.

50

D.

69

#### SOLUTION

Solution : A

5ab=5×a×b
Given, a = 3, b = 2

5ab =5×3×2=30

2x and (12) are ___ of the algebraic expression (2x12).

#### SOLUTION

Solution :

The 'term' of an algebraic expression is either a single number or variable, or number and variables multiplied together.
When such terms are added, it forms an algebraic expression.
So, 2x and (12) are terms of the algebraic expression (2x12).
Here, we should notice that ‘minus’ is associated with the terms.

Perimeter of a square plot with side 2x is 40 units. Find the length of the side of the square plot.

A.

5 units

B.

16 units

C.

10 units

D.

20 units

#### SOLUTION

Solution : C

Perimeter of square = 40 units
4× side = 40
4×2x = 40
8x = 40

So, x = 5 units.

So, the length of each side is 5×2 =  10 units.

In the options given below, there are a few terms picked from an algebraic expression in x and y.
Which of them is/are variable?

A.

xy

B.

4x+6y

C.

pxy

D.

7

#### SOLUTION

Solution : A, B, and C

A constant is a number on its own which has a fixed value whose value does not change.
In the given options the values  of  'xy', '4x+6y' and 'pxy' are not fixed and can change depending on which value 'x' and 'y' takes, but '7' is a fixed value.
So '7' is a constant and others are variables.

The coefficient of xy in the expression '12xy + 6' is ___

#### SOLUTION

Solution : In the expression '12xy + 6', 'xy' is the variable part and it is multiplied to a constant part, which is called co-efficient of the variable.
In this case the coefficient of xy is 12.

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

A.

9x2+9y+5z2+10p

B.

11x2+2y+10z2+10p

C.

9x2+12y+5z2+10p

D.

19x2+10y+5z2+10p

#### SOLUTION

Solution : A

Given expression is
2x
2+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