Предмет: Алгебра, автор: whitechocolate3

Решите пожалуйста систему уравнений. Буду очень благодарна.
103(х+у)=30
4(х-у)=28. 

Ответы

Автор ответа: twilight16
0
103(х+у)=30 уравнение умножим на 3
4(х-у)=28 уравнение разделим на 4, получим
10(x+y)=90
x-y=7 x=7+y
10 (7+y+y)=90
70+20y-90=0
20y=160
y=8
x=7+8=15,
Ответ:(15;8)
Предыдущий вопрос
Следующий вопрос
Похожие вопросы
Предмет: Английский язык, автор: katerina94000
Помогите с английским.
Текст Peter was ten years old and he went to the City School. He was very good at football, so he was in his school team. He always played very well and bravely in practice games and in matches, and he scored plenty of goals. Peter's grandfather and grandmother usually came to see him when there was a match, and they were always happy when other people said, "Your grandson piays very well, doesn't he?" Then one day Peter said to his grandmother, "We're practis- ing for our big match next Saturday. Our school's going to play against the Garden School. They have the best team in our city, so perhaps they'll beat us. Can you come and see the match?" "Oh, yes," his grandmother answered, "your grandfather and I will be there-and I'm certain that you'll beat the Garden School." "Well, I hope we will," Peter answered. The match was in the park, and it began at half past two on Saturday. The Garden School team wore orange shirts, light blue shorts and orange socks, and Peter's team wore dark blue and white shirts, white shorts and dark blue socks. In the first two minutes of the match, the Garden School boys came very close to the City School's goal, but then the goal- keeper kicked the ball to Peter in the middle of the field, and Peter ran with it and kicked it straight into the goal. All the City School boys as well as their families were very happy to see it. After he had scored once, Peter scored twice again before half time. Then in the second half of the match he nearly scored another goal, but he hardly touched the ball with his foot, and the goalkeeper caught it easily and threw it out again. After the match, Peter's grandfather said to him, "You missed a good chance to score a fourth goal then, Peter. If you'd kicked the ball hard, you'd have got a goal easily. Why did you kick it weakly?" "Because there were tears in the goalkeeper's eyes," Peter answered.
Задание к тексту в комментарии
6 лет назад
Предмет: Математика, автор: kazizoverasyl0
Переместительное и сочетательное свойства умножения рациональных чисел. Урок 3
Вычисли удобным способом.
200*(1\200-1\20+1\10-1\8+1\4-1\25)
Помогите мне нужен верный ответ
6 лет назад
Предмет: История, автор: slepichkosophia
в каком году русские поселения начали добычу соли​
6 лет назад
Предмет: Алгебра, автор: AlexTsoy

1.Решите уравнение

4^{x^{2}-8x+12}=frac{1}{64}

2. Найдите значение выражения

(sqrt{11})^{log_{11}25}+6^{log_{(sqrt{6})}11

 
9 лет назад
Предмет: Алгебра, автор: Серега2014

упростите выражение,используя формулы сокращенного умножения (2р-3)(2р+3)+(р-2)в квадрате
9 лет назад