Let's begin by listing out the given information:
This is a 45-45-90 triangle having sides 1:1:2
To calculate for tan 45°, we will solve as shown below:
[tex]\begin{gathered} tan\theta=\frac{opposite}{adjacent} \\ \theta=45\degree \\ opposite=1 \\ adjacent=1 \\ tan45\degree=\frac{1}{1}=1 \\ \therefore tan45\degree=1 \\ \end{gathered}[/tex]
Therefore, D is the answer
