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Having a hard time implementing this theorem on the problem shown above.
http://prntscr.com/arzo8v

Question

http://prntscr.com/arzo2a
Having a hard time implementing this theorem on the problem shown above. 
http://prntscr.com/arzo8v

anonymous · Answer

you need the other side of the triangle, which is also the height of the rectangle 
use pythagoras

anonymous · Answer

if you call it $x$ you can find it via $$x^2+4^2=8^2$$

kikuo · Answer

@satellite73 

Sorry, I'm a bit confused about what you're doing?

kikuo · Answer

Oh, I see what you're saying!

kikuo · Answer

I got 6.9. 

@satellite73

kikuo · Answer

Fr the height

anonymous · Answer

ok then compute the area of the rectangle, base times height, and the area of the triangle, one half base times height, then add the areas

triciaal · Answer

do you need more help or did you forget to close?

kikuo · Answer

Forgot to close! Thanks! I do have one other questions however. I'll tag you in it tri. : ) 
@triciaal

kikuo · Answer

@satellite73 

Oh, I just noticed something. 

It says trapezoid. Not a rectangle?

kikuo · Answer

The area for that 1/2h(b1+b2), but when I calculate it with 6.9 I get the wrong answer.

triciaal · Answer

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