What is $\infty - 0.5\infty$?

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I just confused myself trying explain "infinity" to my daughter.

Infinity and a half is infinity. Check.

Half of infinity is infinity. Check.

Infinity minus half infinity is...what?

I get that $\infty-\infty$ is indeterminate, but Inf*(1-0.5) is obviously infinity. So I guess factoring out infinities is a no-go. That's fine. What about taking the limit?

$$\lim_{x\to\infty} x - 0.5x=\infty$$

Is that right? If it is, why is that not equivalent to $\infty-0.5\infty$?