Given the system of equations
$$\frac{x}{1000} - 0.0024 y = 0.022186$$
$$- 0.0024 x + 0.007467 y = -0.0643$$
Let's express from equation 1 x
$$\frac{x}{1000} - 0.0024 y = 0.022186$$
Let's move the summand with the variable y from the left part to the right part performing the sign change
$$\frac{x}{1000} = 0.0024 y + 0.022186$$
$$\frac{x}{1000} = 0.0024 y + 0.022186$$
Let's divide both parts of the equation by the multiplier of x
/ x \
|----|
\1000/ 0.022186 + 0.0024*y
------ = -------------------
1/1000 1/1000
$$x = 2.4 y + 22.186$$
Let's try the obtained element x to 2-th equation
$$- 0.0024 x + 0.007467 y = -0.0643$$
We get:
$$0.007467 y - 0.0024 \left(2.4 y + 22.186\right) = -0.0643$$
$$0.001707 y - 0.0532464 = -0.0643$$
We move the free summand -0.0532464000000000 from the left part to the right part performing the sign change
$$0.001707 y = -0.0643 + 0.0532464$$
$$0.001707 y = -0.0110536$$
Let's divide both parts of the equation by the multiplier of y
$$\frac{0.001707 y}{0.001707} = - \frac{0.0110536}{0.001707}$$
$$1 y = -6.47545401288811$$
Because
$$x = 2.4 y + 22.186$$
then
$$x = \left(-6.47545401288811\right) 2.4 + 22.186$$
$$x = 6.64491036906854$$
The answer:
$$x = 6.64491036906854$$
$$1 y = -6.47545401288811$$