Mathematics
Assertion (A) : (2x + 5)2 - (2x - 5)2 = 40 is a linear equation in terms of one variable.
Reason (R) : An equation in which the greatest exponent of the variable after simplification is one is called a linear equation.
Both A and R are correct, and R is the correct explanation for A.
Both A and R are correct, and R is not the correct explanation for A.
A is true, but R is false.
A is false, but R is true.
Answer
An equation in which the greatest exponent of the variable after simplification is one is called a linear equation.
This definition aligns with the standard definition of a linear equation. A linear equation in one variable is of the form ax + b = 0, where a ≠ 0 and the highest power of x is 1.
So, reason (R) is true.
Given,
⇒ (2x + 5)2 - (2x - 5)2 = 40
⇒ 4x2 + 25 + 20x - (4x2 + 25 - 20x) = 40
⇒ 4x2 + 25 + 20x - 4x2 - 25 + 20x = 40
⇒ 40x = 40
⇒ 40x - 40 = 0
The above equation is in the form ax + b = 0, where a = 40, b = -40 and the highest power of x is 1.
So, assertion (A) is true.
∴ Both A and R are correct, and R is the correct explanation for A.
Hence, option 1 is the correct option.