If $x + y = 7$ and xy = 12,the value of $(x^2 + y^2)$ is :

If $x + y = 7$ and xy = 12,
the value of $(x^2 + y^2)$ is :

A. 25

B. 29

C. 37

D. 49

Answer: A . 25

Justification:

-> $x^2 + y^2$ $$= (x + y)^2 - 2xy $$ $$=7^2 - 2(12)$$ $$= (49 - 24)= 25$$