1. **State the problem:** We are given the system of equations:
$$5x + 14y = 45$$
$$10x + 7y = 27$$
We need to find the value of the product $xy$ where $(x,y)$ is the solution.
2. **Use the elimination method:** Multiply the first equation by 2 to align coefficients of $x$:
$$2(5x + 14y) = 2(45) \Rightarrow 10x + 28y = 90$$
3. **Subtract the second equation from this new equation:**
$$\cancel{10x} + 28y - (\cancel{10x} + 7y) = 90 - 27$$
$$28y - 7y = 63$$
$$21y = 63$$
4. **Solve for $y$:**
$$y = \frac{63}{21} = 3$$
5. **Substitute $y=3$ into the first original equation:**
$$5x + 14(3) = 45$$
$$5x + 42 = 45$$
6. **Solve for $x$:**
$$5x = 45 - 42 = 3$$
$$x = \frac{3}{5}$$
7. **Calculate the product $xy$:**
$$xy = \frac{3}{5} \times 3 = \frac{9}{5}$$
**Final answer:**
$$\boxed{\frac{9}{5}}$$
Solve System 51E504
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