Центр шара лежит в точке, равноудалённой от сторон треугольника, образуя вместе с вершинами треугольника треугольную пирамиду с равными апофемами. апофемы равны, значит основание высоты пирамиды лежит в центре вписанной в основание пирамиды окружности. площадь основания можно вычислить по формуле герона: s=√(p(p-a)(p-b)(p- где р=(a+b+c)/2. подставив числовые значения a=13, b=14 и с=15 получим s=84 см. радиус вписанной окружности: r=s/p=2s/(a+b+c). r=2·84/(13+14+15)=4 см. высота пирамиды, проведённая к данному треугольнику - это расстояние от центра шара до треугольника. в прямоугольном треугольнике, образованном высотой пирамиды, апофемой и найденным радиусом, высота по теореме пифагора равна: h=√(l²-r²), где l- апофема пирамиды (равна радиусу шара). h=√(5²-4²)=3 см - это ответ.
At the beginning of the day, Margaret had 72 ice cream cones. By noon, she had $\frac{2}{3}$ as many cones as she had at the beginning of the day. By the end of the day, she only had $\frac{2}{3}$ as many cones as she had at noon. How many ice cream cones does she have at the end of the day?
Объяснение:
At the beginning of the day, Margaret had 72 ice cream cones. By noon, she had $\frac{2}{3}$ as many cones as she had at the beginning of the day. By the end of the day, she only had $\frac{2}{3}$ as many cones as she had at noon. How many ice cream cones does she have at the end of the day?
At the beginning of the day, Margaret had 72 ice cream cones. By noon, she had $\frac{2}{3}$ as many cones as she had at the beginning of the day. By the end of the day, she only had $\frac{2}{3}$ as many cones as she had at noon. How many ice cream cones does she have at the end of the day?
Объяснение:
At the beginning of the day, Margaret had 72 ice cream cones. By noon, she had $\frac{2}{3}$ as many cones as she had at the beginning of the day. By the end of the day, she only had $\frac{2}{3}$ as many cones as she had at noon. How many ice cream cones does she have at the end of the day?