Ummm I just need to answer questions sorry!!!
This is the answer in exact form
Given: ∠JNL and ∠MNK are vertical angles and m∠MNK=90°
Prove: ∠JNL is a right angle.
Statements Reasons
1. ∠JNL and ∠MNK are vertical angles. Given
2.
Vertical angle theorem
3.
Angle congruence postulate
4.
Given
5.
<u> Substitution Property of Equality</u>
Since, the measures of angle JNL and MNK are equal and the measure of angle MNK is 90 degrees. therefore, by substitution property of equality, both the angles JNL and MNK will have an equal measure.
Therefore, 
6. ∠JNL is a right angle. Definition of right angle
First you would have to find the base which would be 9^2 + 9^2= C^2 because of the pythagorean theorem. So the base would equal 12.7. To find the area of a triangle it’s A= h•b / 2. So your answer would be 95.25