1. **State the problem:** Solve the system of linear equations:
$$\begin{cases} a + b + c = 22.3 \\ 3a - b - 6c = -11.8 \\ 2a + b - c = 24.7 \end{cases}$$
2. **Write the system in matrix form:**
$$\left[\begin{array}{ccc|c} 1 & 1 & 1 & 22.3 \\ 3 & -1 & -6 & -11.8 \\ 2 & 1 & -1 & 24.7 \end{array}\right]$$
3. **Use substitution or elimination to solve:**
From the first equation:
$$b = 22.3 - a - c$$
Substitute into the second and third equations:
Second equation:
$$3a - (22.3 - a - c) - 6c = -11.8$$
Simplify:
$$3a - 22.3 + a + c - 6c = -11.8$$
$$4a - 22.3 - 5c = -11.8$$
$$4a - 5c = 22.3 - 11.8 = 10.5$$
Third equation:
$$2a + (22.3 - a - c) - c = 24.7$$
Simplify:
$$2a + 22.3 - a - c - c = 24.7$$
$$a + 22.3 - 2c = 24.7$$
$$a - 2c = 24.7 - 22.3 = 2.4$$
4. **Solve the two equations:**
$$\begin{cases} 4a - 5c = 10.5 \\ a - 2c = 2.4 \end{cases}$$
Multiply the second equation by 4:
$$4a - 8c = 9.6$$
Subtract this from the first:
$$ (4a - 5c) - (4a - 8c) = 10.5 - 9.6$$
$$4a - 5c - 4a + 8c = 0.9$$
$$3c = 0.9$$
$$c = 0.3$$
5. **Find $a$ using $a - 2c = 2.4$:**
$$a - 2(0.3) = 2.4$$
$$a - 0.6 = 2.4$$
$$a = 3$$
6. **Find $b$ using $b = 22.3 - a - c$:**
$$b = 22.3 - 3 - 0.3 = 19$$
**Final answer:**
$$a = 3, \quad b = 19, \quad c = 0.3$$
Solve Linear System F7Fabe
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