Ineed finding the reference angles for these angles.
1) 1.4
2)
3) 2.3
4)

Convert the angles to degrees. Remember there are 2pi radians in a circle, and a circle has 360 degrees, so conversion factor is 180degrees/pi. Then you can easily approximate the reference angle. Remember you make the reference angle from the positive x-axis and the reference angle will be the angle between the terminal side and the nearest x-axis (either positive side or negative side of the x-axis).
1)
2)

Answer 20 centimeters15+8=2323-3=20so the answer is 20 centimeters

3x+9+4x+x=8x+9that's the answer for your question.