Answer:
The length of the unknown sides of the triangles are as follows:
CD = 10√2
AC = 10√2
BC = 10
AB = 10
ΔACD is a right angle triangle. Therefore, Pythagoras theorem can be used to find the sides of the triangle.
c² = a² + b²
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 / √2 × 20
CD = 20 / √2 = 20√2 / 2 = 10√2
20² - (10√2)² = AC²
400 - 100(2) = AC²
AC² = 200
AC = √200 = 10√2
ΔABC is a right angle triangle too. Therefore,
AB² + BC² = AC²
Using trigonometric ratio,
cos 45 = BC / 10√2
BC = 10√2 × cos 45
BC = 10√2 × 1 / √2
BC = 10√2 / √2 = 10
(10√2)² - 10² = AB²
200 - 100 = AB²
AB² = 100
AB = 10
Step-by-step explanation:
