Вопрос по математике:

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Самостоятельная работа по теме

«Простейшие задачи в координатах»

Вариант 22.

Дано: А(4 ; - 15), В(-8;-5), С(5 ;0).

Найти: а) координаты вектора АС;

б) длину вектора ВС;

в) координаты середины отрезка АВ;

г) периметр треугольника АВС;

д) длину медианы СМ.

ответ по ссылке: https://tex.z-dn.net/?f=A%284%2C-5%29%5C%3B+%2C%5C%3B+%5C%3B+B%28-8%2C-6%29%5C%3B+%2C%5C%3B+%5C%3B+C%285%2C9%29%5C%5C%5C%5C1%29%5C%3B+%5C%3B+%5Coverline+%7BAC%7D%3D%285-4%2C9-%28-5%29%29%3D%281%2C14%29%5C%5C%5C%5C2%29%5C%3B+%5C%3B+%5Coverline+%7BBC%7D%3D%2813%2C15%29%5C%5C%5C%5C%7C%5Coverline+%7BBC%7D%7C%3D%5Csqrt%7B13%5E2%2B15%5E2%7D%3D+%5Csqrt%7B394%7D+%5C%5C%5C%5C3%29%5C%3B+%5C%3B+x_%7BM%7D%3D+%5Cfrac%7Bx_%7BA%7D%2Bx_%7BB%7D%7D%7B2%7D%3D+%5Cfrac%7B4-8%7D%7B2%7D%3D-2%5C%3B+%2C%5C%5C%5C%5Cy_%7BM%7D%3D%5Cfrac%7By_%7BA%7D%2By_%7BB%7D%7D%7B2%7D%3D++%5Cfrac%7B-5-6%7D%7B2%7D%3D-5%2C5%5Cquad++%5Cto+%5Cquad+M%28-2%3B%5C%3B+-5%2C5%29%5C%5C%5C%5C4%29%5C%3B+%5C%3B+%0A%5Coverline%7BAB%7D%3D%28-8-4%2C-6%2B5%29%3D%28-12%2C-1%29%5C%5C%5C%5C%7C%5Coverline+%7BAB%7D%7C%3D%5Csqrt%7B12%5E2%2B1%5E2%7D%3D%5Csqrt%7B145%7D%5C%5C%5C%5C%7C%5Coverline%7BAC%7D%7C%3D%5Csqrt%7B1%5E2%2B14%5E2%7D%3D%5Csqrt%7B197%7D%5C%5C%5C%5CP_%7BABC%7D%3D+%5Csqrt%7B145%7D%2B%5Csqrt%7B197%7D%2B%5Csqrt%7B394%7D+