Set 14: Linear Equations (Advanced)

Choice A is correct. Choice C is the correct answer. 1. Start with the equation: $9x - 18 = 27$ 2. Add 18 to both sides: $9x = 27 + 18$ 3. Simplify: $9x = 45$ 4. Divide both sides by 9: $x = \frac{45}{9}$ 5. Simplify: $x = 5$ 6. Verify: $9(5) - 18 = 45 - 18 = 27$ ✓ Choice B is incorrect because this results from subtracting 18 from 27: $9$, then $9 /9 = 1$. We must add to undo subtraction. Choice D is incorrect because this is the value of $9x$. Don't stop early! Choice C is incorrect because this results from multiplying 45 by 9: $405$.