Nature gives man everything necessary for its existence. but often we do not appreciate these gifts did not hesitate to tear away the flowers and branches of trees, without giving anything in return. we think that it is a trifle, because the new grow. turning around, hard to miss - how all the same beautiful nature. we just need to learn to appreciate it! nature delights us with its unusual and so different seasons. in the spring, as if making the first steps, nature refreshed, shoots appear on the earth, for them - the first leaves on the trees. by the summer, in the woods and gardens present a riot of colors, flourished flowers and shrubs.autumn treetops sometimes crimson and gold fireworks decorate the alleys and parks. golden autumn harbors all around the yellow carpet of fallen leaves. the arrival of winter is replaced by rain on snow. lake shackles ice, trees wraps in white coats. in his tenure comes to the queen of winter and spring nature as if asleep.in any season, nature is unique and extraordinarily beautiful.in recent years, the protection of nature is receiving attention. this is good, and then it becomes more and more people who care about the future of our planet, showing care and concern for the surrounding nature. protect and preserve the pristine beauty of the native land -it is our common duty to you and the duty!
1. пусть s — площадь ромба, d₁, d₂ и a — его диагонали и сторона соответсвенно. тогда s = 0.5d₁d₂ ⇔ 19.2 = 3.2d₁ ⇔ d₁ = 6 м. диагонали ромба делят фигуру на 4 равных прямоугольных треугольника с катетами 0.5d₁ и 0.5d₂, то есть 3 метра и 1.6 метра. по теореме пифагора гипотенуза «a» в таком треугольнике равна 4.8 м. тогда периметр ромба p равен 4a = 19.2 (м²). ответ: 19.2 м². 2. пусть s — площадь ромба, d₁, d₂. тогда d₁/d₂ = 3/4, откуда d₂ = 4d₁/3. в то же время площадь ромба s равна 0.5d₁d₂ = 0.5d₁·4d₁/3 = 2d₁²/3. решая уравнение s = 2d₁²/3 = 54 относительно d₁, получаем, что d₁ = 9 см. тогда d₂ = 4d₁/3 = 4·9/3 = 12 см. ответ: 9 см и 12 см.