http://thinkzone.wlonk.com/MathFun/Triangle.htm

Look on that site.

Using only elementary geometry determine the value of the angle marked “x.”

http://thinkzone.wlonk.com/MathFun/Triangle1.gif

For the purpose of this let’s call the vertex of the lowermost triangle point “f.”

So there are a few easy bits. Angle AFB is 50 degrees because the angle sum of any triangle is 180, subtract the sum of seventy and sixty, and then Angle DFE is also 50 degrees because it’s vertically opposite to AFB.

Thus it stands that angle X is equal to 180 - (50 + angle FDE) but you still need FDE.

…I cannot find Angle FDE. >.>

I’ve tried everything. I’ve used every triangle visible and every geometric convention or technique or whatever to no avail. FDE eludes me.

We also know that AEB is 30 (angle sum again) and that angle EDB can give us x by subtracting 30 from it but again I’m screwed over the lack of a value for FDE- or EDB in this case. Whichever, same angle.

I know that ADB is 40 (angle sum again) and ACB is 20 (angle sum) and every other frickin’ value but FDE/EDB/CDB.

Mathematics people, halp! This is something I enjoy doing in my free time but this one drives me up a wall.

*I can’t solve it.* ;W; Halp plox. I am a pleb. Enlighten me.