Can anyone help me with my math HW? I have to find the length DE.
Figure not drawn to scale.
can we assume that AE and BE are the same length? if so, DE should be 4cm.
Nope the triangle in the middle is not isosceles
Global rule 2 etc.
Solving for (where [math]\alpha = AED [/math]:
[math]DE = \frac{9\cos \alpha}{\sin \alpha} [/math]
Where [math]\alpha [/math] is such that [math] \sin \left(2\alpha - \frac{\pi}{4} \right) = \frac{5}{4\sqrt{2}} [/math]
Solve for alpha by putting that into Wolfram Alpha, then plug that into the equation for DE
You get DE around 6.6
I'll post general working out soon
>>126878
part 1
if any of this goes over your head completely (i.e. not familiar at all) then you cannot do this question
>>126886
