45 i believe it is i may be wrong!!!
The answer must be

since the triangular pyramid has 4 faces and each has an area of 30

we should multiply that by 4 , so :
Answer:
x° = 67°
Step-by-step explanation:
1. The first three diagrams are showing you that opposite exterior angles are congruent. Based on that, when you are faced with opposite exterior angles in the fourth diagram, you are able to conclude they are congruent. That means x° = 67°.
2. You can determine the other angles in the figure based on linear angles being supplementary, and same-side interior angles being supplementary. After you work through all the angles, you find that x = 67.
In form ax + b = c: 2x - 8.4 = 5
Solution to equation: x = 6.7
Step-by-step explanation:
4x - 8.4 = 2x + 5
2x - 8.4 = 5
2x = 13.4
x = 6.7