Question

The expanded form of an expression is $x^2+y^2+z^2+2xy+2yz+2zx$. Which of the following is the expression?

• A. ${(-x+y+z)}^2$
• B. ${(x-y-z)}^2$
• C. ${(x+y-z)}^2$
• D. ${(x+y+z)}^2$

Answer 1

The correct option is D ${(x+y+z)}^2$

${(x+y+z)}^2=x^2+y^2+z^2+2xy+2yz+2zx$.

$\therefore {(x+y+z)}^2$ is the required expression.