Answer:
Length DE= 2√2
Length EF= 2√2
Step-by-step explanation:
The 45-45-90 rule is very special but this question is really simple. You have all the angles and one side.
STEPS:
1) Take 45 from angle D and use its sine to find side EF
2) sin45= x/4 => 2.82 or 2√2
3) Take either cos45 from angle D or use Pythagoras since we now have enough side lengths to use Pythagoras (faster for me to use cosine).
4) cos45=x/4 => 2.82 or 2√2
Further explanation:
If you don't understand the sine and cosines, here's a word play to help.
S O/H
C A/H
T O/A
S=Sine
C=Cosine
T= Tangent
O= Opposite
H= Hypotenuse
A= Adjacent
If you search a video on this word play it will help more since it is visual.
Good luck.
