Set 16: Linear Equations

Choice B is correct. Choice C is the correct answer. When an equation equals zero, we solve using the same strategy. 1. Start with the equation: $x - 9 = 0$ 2. Add 9 to both sides: $x = 0 + 9$ 3. Simplify: $x = 9$ 4. Verify: $9- 9 = 0$ ✓ This demonstrates a simple principle: when $x - a = 0$, the solution is always $x = a$. This is because only $a - a = 0$. Zero Equations: The equation $x - a = 0$ is equivalent to $x = a$. Any number minus itself equals zero. Choice C is incorrect because zero is the result of the equation, not the value of $x$. Don't confuse the right side with the solution. Choice D is incorrect because this is the negative of the correct answer. There's no mathematical justification for $x = -9$ here. Choice A is incorrect because 1 is not relevant to this problem. This might result from confusing different mathematical concepts.