Question

3x-y=7 2x+3y=1 система способом постановки

Answer 1

3x-y=7    ⇒   у=3х-7

2x+3y =1

2х +3 (3х-7) =1

2х + 9х - 21  = 1

11х = 1 + 21

11х = 22

х = 22 : 11

х = 2

у  = 3 * 2  -  7  = 6  -  7

у  = - 1

Answer 2

To solve the system of equations:

1. 3x - y = 7
2. 2x + 3y = 1

You can use the method of substitution or elimination. Let's use the method of substitution.

Step 1: Solve one of the equations for one of the variables in terms of the other variable. Let's solve equation (1) for y:

1. 3x - y = 7 y = 3x - 7

Step 2: Substitute the expression for y (from step 1) into the other equation (equation 2):

2x + 3(3x - 7) = 1

Step 3: Solve for x:

2x + 9x - 21 = 1 11x - 21 = 1

Step 4: Isolate x:

11x = 1 + 21 11x = 22 x = 22 / 11 x = 2

Step 5: Now that we have the value of x, we can find y by substituting the value of x into either of the original equations. Let's use equation (1):

3x - y = 7 3(2) - y = 7 6 - y = 7

Step 6: Solve for y:

-y = 7 - 6 -y = 1

Step 7: Isolate y:

y = -1

So, the solution to the system of equations is x = 2 and y = -1.