Question

How do you solve the system `0.4x-0.1y=2, 0.2x+0.5y=1`?

Answer 1

See explanation.

Explanation:

The starting system is:

`{ (0.4x-0.1y=2),(0.2x+0.5y=1):}`

If we multiply the second equation by `-2` the coefficients of `x` will be opposite numbers:

`{ (0.4x-0.1y=2),(-0.4x-y=-2):}`

Now we can add both sides of the equations to get an euation of 1 variable:

`-1.1y=0`

`y=0`

Now we have to substitute the calculated value of `y` to calculate `x`:

`0.4x=2`

`x=2/0.4=20/4=5`

Answer:

The solution of this systemm is:

`{(x=5),(y=0):}`