Question

Pick the equation which has the solution in the form of prime number.

(a) 2x = 3

(b) 3z = -6

(c) 4y – 3 = 2

(d) 2z – 2 = 2

The question was asked during an interview.

The above asked question is from Solving Linear Equations with Variables on One Side and Number on the Other in portion Linear Equations in One Variable of Mathematics – Class 8

Answer 1

Right choice is (d) 2z – 2 = 2

For explanation: A prime number is the number which can be formed by multiplying only two numbers which are 1 and the number itself.

Solving equation, 2z – 2 = 2

Step 1: Transposing – 2 on RHS we get,

2z = 4

Step 2: Dividing equation by 2 we get,

z = 2

Since 2 is greater than 0 and can be formed only by multiplying 1 and 2 it is a prime number.