I'm pretty stuck on some of these quadrilaterals... Imageshack - 38928686.jpg

The first one is a parallelogram, the only angle I can find is angle b which is 80, how would find angle a and c?

The second one is also a parallelogram, but I don't know what to do here. I don't know how to find y or x in this problem.

The last one is a kite. FH = 16 in, FH & EG intersects at L, and EG = 20 in, angle FEH = 60degrees.

The main thing I don't get here is find the measure of the lines what does line EF =? And what does FG =? Also how did you find this? One last thing would angle EFG = 60?

2. Originally Posted by Jubbly
I'm pretty stuck on some of these quadrilaterals... Imageshack - 38928686.jpg

The first one is a parallelogram, the only angle I can find is angle b which is 80, how would find angle a and c?

The second one is also a parallelogram, but I don't know what to do here. I don't know how to find y or x in this problem.

The last one is a kite. FH = 16 in, FH & EG intersects at L, and EG = 20 in, angle FEH = 60degrees.

The main thing I don't get here is find the measure of the lines what does line EF =? And what does FG =? Also how did you find this? One last thing would angle EFG = 60?

Hi jubbly,

In the first one, it seems to me that angle c is part of a linear pair with 80 degrees, so it must be supplementary to 80 degrees.

And angle a is an alternate interior angle to the 47 degree angle and we know that the alternate interior angles are congruent.

On the second parallelogram, remember that the diagonals bisect each other.

3y + 13 = 2y + 37

Solve the above one for y, and substitute it into this one.

3y = 2x - 4

In the kite, triangle FEH is isosceles and since the vertex angle FEH = 60, it is also equilateral. This means FH = EF = EH = 16.

Also, FL = HL = 8 because EG bisects FH.

Using the 30-60-90 rule, you can easily find EL = $8\sqrt{3}$. Subtract that from 20 to get LG. Then use the pythagorean theorem to find FG.

I think I've answered your last question, but angle EFG does not equal 60 degrees. Angel EFH = 60 degrees. Using trig, it's somewhere around 97.5 degrees, but that's not important here.