−<span>3<span>(<span><span>4a</span>−<span>5b</span></span>)</span></span><span>=<span><span>(<span>−3</span>)</span><span>(<span><span>4a</span>+<span>−<span>5b</span></span></span>)</span></span></span><span>=<span><span><span>(<span>−3</span>)</span><span>(<span>4a</span>)</span></span>+<span><span>(<span>−3</span>)</span><span>(<span>−<span>5b</span></span>)</span></span></span></span><span>=<span><span>−<span>12a</span></span>+<span>15<span>b</span></span></span></span>
The answer is: [D]: 2x + 22 .
______________________________________________
The answer is zero.
If any of the pairs of lines were parallel, there would be some same-side interior angles or such that would be supplementary. However, since the lines are not parallel lines crossed by a transversal, the only ones guaranteed to be supplementary to angle 7 are the ones adjacent to it that form a linear pair.