Question

Срочно! Даю 50 баллов!

Answer 1

$x^2+2ax+a^2=(x+a)^2\\\\b=2a\; \; \to \; \; a=\frac{b}{2}\; \; \to \; \; a^2=(\frac{b}{2})^2=\frac{b^2}{4}\\\\\\x^2+bx+\frac{b^2}{4}=(x+\frac{b}{2})^2$