1. **State the problem:** Find the lowest common multiple (LCM) of 6 and 8.
2. **Formula and rules:** The LCM of two numbers is the smallest positive integer divisible by both numbers. To find it, we can use the prime factorization method or the formula:
$$\text{LCM}(a,b) = \frac{|a \times b|}{\text{GCD}(a,b)}$$
where GCD is the greatest common divisor.
3. **Calculate GCD of 6 and 8:**
- Prime factors of 6: $2, 3$
- Prime factors of 8: $2, 2, 2$
- Common prime factors: $2$
- So, $\text{GCD}(6,8) = 2$
4. **Calculate LCM:**
$$\text{LCM}(6,8) = \frac{6 \times 8}{2} = \frac{48}{2} = 24$$
5. **State the problem:** Solve the simultaneous equations:
$$6x + 7y = 27$$
$$8x + 11y = 41$$
by first multiplying each equation by a different constant so that the coefficient of $x$ in both equations is 24 (the LCM from part a).
6. **Multiply equations:**
- Multiply the first equation by 4:
$$4 \times (6x + 7y) = 4 \times 27 \Rightarrow 24x + 28y = 108$$
- Multiply the second equation by 3:
$$3 \times (8x + 11y) = 3 \times 41 \Rightarrow 24x + 33y = 123$$
7. **Subtract the first new equation from the second to eliminate $x$:**
$$ (24x + 33y) - (24x + 28y) = 123 - 108 $$
$$ 5y = 15 $$
$$ y = 3 $$
8. **Substitute $y=3$ into the first original equation:**
$$ 6x + 7(3) = 27 $$
$$ 6x + 21 = 27 $$
$$ 6x = 6 $$
$$ x = 1 $$
**Final answer:**
$$\text{LCM}(6,8) = 24$$
$$x = 1, y = 3$$
Lcm Simultaneous 1Fd169
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