Question

7 x + 2y=117x+6y=-9​

Answer 1

Ответ:

7х+2у=1/•(-3) -21х-6у=-3 -21х=-3

+

17х+6у=-9 17х+6у=-9 17х=-9

-4х=-12

х=3

7×3+2у=1

2у=1-21

у=-10

ответ: (3;-10)

Answer 2

To solve the system of equations:

7x + 2y = 11
7x + 6y = -9

There are multiple methods to solve this system, such as substitution, elimination, or matrix methods. I will use the elimination method to solve it.

First, let's multiply the first equation by 3 to make the coefficients of y in both equations equal:

3(7x + 2y) = 3(11)
21x + 6y = 33

Now we have:

21x + 6y = 33
7x + 6y = -9

Next, subtract the second equation from the first equation to eliminate y:

(21x + 6y) - (7x + 6y) = 33 - (-9)
21x + 6y - 7x - 6y = 33 + 9
14x = 42
x = 42/14
x = 3

Now substitute the value of x into either of the original equations. Let's use the first equation:

7x + 2y = 11
7(3) + 2y = 11
21 + 2y = 11
2y = 11 - 21
2y = -10
y = -10/2
y = -5

Therefore, the solution to the system of equations is x = 3 and y = -5.