Question

3x+2 y=8, х- 3 у =21 ​

Answer 1

Ответ:

Объяснение:

1)3х+2у=8

3х+2у-8=8-8

3х+2у-8=0

2)х-3у=21

Х-3у-21=21-21

Х-3у-21=0

Answer 2

To solve this system of linear equations:

1. 3x + 2y = 8
2. x - 3y = 21

You can use either the substitution method or the elimination method. I'll use the elimination method here:

First, multiply the second equation by 3 to make the coefficients of y in both equations cancel each other out when added together:

1. 3x + 2y = 8
2. 3(x - 3y) = 3(21)

Now you have:

1. 3x + 2y = 8
2. 3x - 9y = 63

Next, subtract equation 2 from equation 1:

(3x + 2y) - (3x - 9y) = 8 - 63

This simplifies to:

11y = -55

Now, divide both sides by 11 to isolate y:

y = -55 / 11 y = -5

Now that you have the value of y, you can substitute it back into either of the original equations to find the value of x. I'll use the first equation:

3x + 2(-5) = 8

Simplify:

3x - 10 = 8

Now, add 10 to both sides:

3x = 18

Finally, divide by 3:

x = 18 / 3 x = 6

So, the solution to the system of equations is x = 6 and y = -5.