Question

Помогите пожалуйста,решить систему способом сложения...Пожалуйста.Помогите:)Специальную скобку как у системы нарисовать не смогу буду без неё! 9х-2у=-17 ии х-2у=7,помогите...

Answer 1

9x - 2y = -17

x - 2y = 7

одно из уравнений оставляем без изменения, а второе переписываем, складывая с первым

(в этом случае лучше из первого вычесть второе уравнение)

x - 2y = 7

(9x - x) - 2y -(-2y) = -17 - 7

--------------------------------------(это разделитель ---скобку системы не нарисовать здесь)

x - 7 = 2y

8x = -24

--------------------------------------

2y = x - 7

x = -3

--------------------------------------

2y = -3 -7

x = -3

-------------------------------------

y = -5

x = -3

Answer 2

Solving the System of Equations using the Method of Addition

To solve the system of equations 9x - 2y = -17 and x - 2y = 7 using the method of addition, we can eliminate one variable by adding the two equations together. This will result in a new equation with only one variable, which can then be solved to find its value. Let's go through the steps:

Step 1: Write down the given system of equations: - Equation 1: 9x - 2y = -17 - Equation 2: x - 2y = 7

Step 2: Multiply one or both equations by a constant, if necessary, to make the coefficients of one of the variables the same or additive inverses of each other. In this case, we don't need to multiply any equation.

Step 3: Add the two equations together to eliminate one variable. The resulting equation will have only one variable: - (9x - 2y) + (x - 2y) = (-17) + 7 - Simplifying the equation, we get: 10x - 4y = -10

Step 4: Solve the resulting equation for the remaining variable. In this case, we solve for x: - 10x - 4y = -10 - Adding 4y to both sides of the equation: 10x = 4y - 10 - Dividing both sides of the equation by 10: x = (4y - 10) / 10 - Simplifying further, we have: x = (2y - 5) / 5

Step 5: Substitute the value of x back into one of the original equations to solve for the other variable. Let's substitute it into Equation 2: - x - 2y = 7 - Substituting the value of x from Step 4: (2y - 5) / 5 - 2y = 7 - Multiplying both sides of the equation by 5 to eliminate the fraction: 2y - 5 - 10y = 35 - Simplifying the equation: -8y - 5 = 35 - Adding 5 to both sides of the equation: -8y = 40 - Dividing both sides of the equation by -8: y = -5

Step 6: Substitute the value of y back into the equation from Step 4 to solve for x: - x = (2y - 5) / 5 - Substituting the value of y from Step 5: x = (2(-5) - 5) / 5 - Simplifying the equation: x = (-10 - 5) / 5 - Further simplification gives us: x = -3

Solution:

The solution to the given system of equations is x = -3 and y = -5.

Please let me know if you need any further assistance!