Question

Решите систему уравнений способом алгебраического сложения.7 класс

Answer 1

Х+4у=5
3х-у=2 домножим почленно на 4

   х+4у=5
12х-4у=8 сложим почленно оба уравнения

х+12х+4у+(-4у)=5+8

13х=13   х=1


1+2у=5

2у=4

у=2

Ответ (1;2)

Answer 2

Solving a System of Equations using Algebraic Addition

To solve a system of equations using the method of algebraic addition, we need to eliminate one variable by adding the equations together. Let's solve the following system of equations:

Equation 1: x + y = 5 Equation 2: x - y = 7

To eliminate the variable "y," we can add the two equations together. Adding Equation 1 and Equation 2 gives us:

(x + y) + (x - y) = 5 + 7

Simplifying the equation, we get:

2x = 12

Now, we can solve for "x" by dividing both sides of the equation by 2:

2x/2 = 12/2 x = 6

Now that we have the value of "x," we can substitute it back into one of the original equations to solve for "y." Let's use Equation 1:

6 + y = 5

Subtracting 6 from both sides of the equation, we get:

y = 5 - 6 y = -1

Therefore, the solution to the system of equations is x = 6 and y = -1.