Quick questions on Data transformation and linearisation (QCE General Mathematics Unit 3)

In General Mathematics you choose from three transformations, applied to either the explanatory variable $x$ or the response variable $y$.

You pick the transformation that makes the transformed scatterplot look most like a straight line. In practice you compare residual plots or the value of $r^2$ for the candidate transformations and select the one with the most random residuals and the highest $r^2$. The transformation can be applied to either axis; sometimes squaring $x$ works while sometimes taking $\log y$ works, so test rather than guess.

If the response was logged, the equation predicts $\log y$, not $y$. You must antilog at the end, or your answer is in the wrong units.