3x-1=77 (due to exterior alternate angle)
Or, 3x=77-1
or, 3x=76
or, x=76/3
or, x=25.3
Answer:
-9
Step-by-step explanation:
= 
the height is 11.25 because 7×4=28×11.25=315
By right triangle trigonometry, the sine of the measure of an angle is the ratio of the opposite side of this angle to the hypotenuse.
Thus,


is a constant which can be found using a calculator:
with calc in pc: view → scientific → 27→sin = 0.45399,
thus x=34/0.45399=74.89
Answer: 74.89