Answer: 10x^2-17x-20
Step-by-step explanation:
The answer is B. The angle next to 100 degrees would be 80 as the angles are supplementary. Then you would add 80 + 70 = 150. All the angles in a triangle add to 180, thus making the "x" angle 30 due to 180 - 150.
Hope this helped :))
I would have to say 2.3 but i dont know the real answer thats what i calculated