1. **State the problem:** We are given a system of linear equations:
$$2x + 3y = 1$$
$$7x + 10y = 5$$
We need to find the value of $$10x_1 + y_1$$ where $$(x_1, y_1)$$ is the solution to the system.
2. **Use the substitution or elimination method:** Here, we use elimination.
3. Multiply the first equation by 7 and the second by 2 to align coefficients of $x$:
$$7(2x + 3y) = 7(1) \Rightarrow 14x + 21y = 7$$
$$2(7x + 10y) = 2(5) \Rightarrow 14x + 20y = 10$$
4. Subtract the second from the first to eliminate $x$:
$$ (14x + 21y) - (14x + 20y) = 7 - 10 $$
$$ 14x - \cancel{14x} + 21y - 20y = -3 $$
$$ y = -3 $$
5. Substitute $y = -3$ into the first original equation:
$$ 2x + 3(-3) = 1 $$
$$ 2x - 9 = 1 $$
$$ 2x = 10 $$
$$ x = \frac{10}{2} = 5 $$
6. Now compute $10x_1 + y_1$:
$$ 10(5) + (-3) = 50 - 3 = 47 $$
**Final answer:**
$$\boxed{47}$$
Linear System Bdbc66
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