Question

Sпрямоугольника=36см^2
Периметр=24см
Найдите его стороны

Answer 1

$S=ab=36\\P=2(a+b)=24\\\\\left \{ {{ab=36} \atop {2(a+b)=24}} \right. =>\left \{ {{ab=36} \atop {a+b=12}} \right. =>a=12-b\\\\(12-b)b=36\\12b-b^2=36\\b^2-12b+36=0\\(b-6)^2=0\\b=6\\\\a=12-b\\a=6$