Question

1)x+y=18x-y=22)y-x=5y+3x=21​

Answer 1

Ответ:

Объяснение:

1) x+y=18

+

x-y=2

2x=20

x=20\2

x=10

y=18-x

y=8

2) не знаю как решать

Answer 2

To solve this system of linear equations, you can use the method of substitution or elimination. I'll show you how to solve it using the elimination method.

The system of equations is:

1. x + y = 18
2. x - y = 22
3. y - x = 5
4. 3x + y = 21

We'll start by eliminating one of the variables. Let's eliminate y. We can do this by adding equation 1 and equation 2:

(x + y) + (x - y) = 18 + 22

Simplify the left side:

2x = 40

Now, divide both sides by 2 to solve for x:

x = 20

Now that we have the value of x, we can substitute it into one of the original equations to find the value of y. Let's use equation 1:

x + y = 18

Substitute x = 20:

20 + y = 18

Now, solve for y:

y = 18 - 20 y = -2

So, the solution to the system of equations is x = 20 and y = -2.