1. **Stating the problem:** You want to solve a linear system where none of the variables have a coefficient of 1.
2. **General approach:** The goal is to isolate variables or eliminate them to find their values. When coefficients are not 1, you can use methods like substitution, elimination, or matrix operations.
3. **Key formula:** For a system like
$$a_1x + b_1y = c_1$$
$$a_2x + b_2y = c_2$$
you can use elimination by multiplying equations to get matching coefficients for one variable.
4. **Example:** Suppose
$$3x + 4y = 10$$
$$5x + 2y = 8$$
To eliminate $x$, multiply the first equation by 5 and the second by 3:
$$5(3x + 4y) = 5(10) \Rightarrow 15x + 20y = 50$$
$$3(5x + 2y) = 3(8) \Rightarrow 15x + 6y = 24$$
5. **Subtract equations:**
$$ (15x + 20y) - (15x + 6y) = 50 - 24$$
$$ \cancel{15x} + 20y - \cancel{15x} - 6y = 26$$
$$14y = 26$$
6. **Solve for $y$:**
$$y = \frac{26}{14} = \frac{13}{7}$$
7. **Substitute back to find $x$:**
Use the first equation:
$$3x + 4\left(\frac{13}{7}\right) = 10$$
$$3x + \frac{52}{7} = 10$$
$$3x = 10 - \frac{52}{7} = \frac{70}{7} - \frac{52}{7} = \frac{18}{7}$$
$$x = \frac{18}{7} \times \frac{1}{3} = \frac{18}{21} = \frac{6}{7}$$
**Summary:** When coefficients are not 1, multiply equations to create matching coefficients, then add or subtract to eliminate variables. Solve for one variable, then substitute back to find others.
Solving Linear Systems 41Fdb0
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.