The length of the unknown sides of the triangles are as follows:
CD = 10â2
AC = 10â2
BC = Â 10
AB = 10
Triangle ACD
ÎACD is a right angle triangle. Therefore, Pythagoras theorem can be used to find the sides of the triangle.
where
c = hypotenuse side = AD = 20
a and b are the other 2 legs
lets use trigonometric ratio to find CD,
cos 45 = adjacent / hypotenuse
cos 45 = CD / 20
CD = 1 / â2 Ă 20
CD = 20 / â2 = 20â2 / 2 = 10â2
20² - (10â2)² = AC²
400 - 100(2)  = AC²
AC² = 200
AC = â200 = 10â2
Triangle ABC
ÎABC is a right angle triangle too. Therefore,
Using trigonometric ratio,
cos 45 = BC / 10â2
BC = 10â2 Ă cos 45
BC = 10â2 Ă 1 / â2
BC = 10â2 / â2 = Â 10
(10â2)² - 10² = AB²
200 - 100 = AB²
AB² = 100
AB = 10
learn more on triangles here: https://brainly.com/question/24304623?referrer=searchResults