Answer:
14
Step-by-step:
A triangle has 3 sides, 2 of which we know and need to use in this question, i.e, 8√7 and X (which we need to solve for).
X is opposite to that 45° angle, which makes it the "opposite" and the 8√7 is the "hypotenuse"
When solving questions like this one, remember the acronym SOH CAH TOA which means: sinσ = [tex]\frac{O}{H}[/tex]
cosσ = [tex]\frac{A}{H}[/tex]
tanσ = [tex]\frac{O}{A}[/tex]
NB: σ= the known angle
