You substitute the y from the second eqaution to the y in the first equation
2x + 6 < x + 20
- x - x
x + 6 < 20
- 6 - 6
x < 14
Solution Set: (-∞, 14)
Answer:
Option B. 
Step-by-step explanation:
we know that
In the right triangle of the figure
The sine of angle theta is equal to divide the opposite side to angle theta by the hypotenuse
so

substitute the given values

using a calculator

-34.68 - (-49.62) = -34.68 + 49.62 = 14.94 degrees warmer at the north pole