{3х-3у=6 {2.3х+3у=21

To solve this system of equations, we can use the method of elimination. Let's start by multiplying the first equation by 2.3 to eliminate the x variable:

2.3(3x - 3y) = 2.3(6) 6.9x - 6.9y = 13.8

Now let's write down the second equation:

2.3x + 3y = 21

Now we can add the two equations together:

(6.9x - 6.9y) + (2.3x + 3y) = 13.8 + 21 9.2x - 3.9y = 34.8

Now we have a new equation:

9.2x - 3.9y = 34.8

We can solve this equation for x:

9.2x = 34.8 + 3.9y x = (34.8 + 3.9y) / 9.2

Now substitute this expression for x into the first equation:

3(34.8 + 3.9y) / 9.2 - 3y = 6

Multiply both sides of the equation by 9.2 to eliminate the fraction:

3(34.8 + 3.9y) - 27.6y = 55.2

Distribute the 3:

104.4 + 11.7y - 27.6y = 55.2

Combine like terms:

-15.9y = -49.2

Divide both sides by -15.9 to solve for y:

y = -49.2 / -15.9 y = 3.08

Now substitute this value for y back into the equation for x:

x = (34.8 + 3.9(3.08)) / 9.2 x = 1.74 + 1.01 x = 2.75

Therefore, the solution to the system of equations is x = 2.75 and y = 3.08.