Answer:
Step-by-step explanation:
this is a 45-45-90 triangle. The angle opposite the 45° angle is also 45°.
HI = HJ because this is an isosceles triangle.
Use the cos function to find the length of HJ:
cos Ф = adj / hyp or adj = (hyp)(cos Ф).
1
Here we have adj = HI = HJ = 4√5 cos 45° = 4√5 · -----
√2, or 4√5 / √2
4√10
This last result simplifies to ----------
2
or 2√10 (answer)
The length of side HJ and that of HI is 2/√10.
