Question

3x + 5y = 375,7x + 4y = 530.​

Answer 1

Ответ:

(50; 45)

Вычитаем из 1-го уравнения 2-е.

Получаем:

(3x-7x)+(5y-4y)=375-530

-4x+y= - 155

y= 4x-155

Подставляем в 1-е уравнение:

3х + 5 (4х-155) = 375

3х + 20х - 775 = 375

23х = 375 + 775

23х = 1150

х = 50

Cледовательно, у = 4*50 - 155 = 200 - 155 =45

Ответ: (50; 45)

Answer 2

To solve the system of equations:

3x + 5y = 375 ...(Equation 1) 7x + 4y = 530 ...(Equation 2)

There are several methods to solve this system of equations, such as substitution, elimination, or matrix methods. Let's use the substitution method to solve it.

First, let's solve Equation 1 for x in terms of y: 3x = 375 - 5y x = (375 - 5y) / 3

Now, substitute this expression for x in Equation 2: 7((375 - 5y) / 3) + 4y = 530

Multiply through by 3 to eliminate the fraction: 7(375 - 5y) + 12y = 1590 2625 - 35y + 12y = 1590 -23y = 1590 - 2625 -23y = -1035 y = (-1035) / (-23) y = 45

Now substitute the value of y back into Equation 1 to find x: 3x + 5(45) = 375 3x + 225 = 375 3x = 375 - 225 3x = 150 x = 150 / 3 x = 50

Therefore, the solution to the system of equations is x = 50 and y = 45.