Question

Which of the following is an identity?

• A. ${(x-2)}^2=x^2-4x+4$
• B. $x^2-4x+4=0$
• C. ${(x+3)}^2=x^2+5x+8$
• D. $2x-1=0$

Answer 1

The correct option is A

${(x-2)}^2=x^2-4x+4$

Solution: If a statement is true for all the values of the variable, such statements are called identities.

B → will be true only when $x=2$

C → will be true only when $x=-1$

D → will be true only when $x=\frac{1}{2}$

But A will be true for all values of $x$.