This is the concept of trigonometry, we are required to calculate the number of floors the building has given the information above; # floors=[height of the building]/[height of each floor] height of each floor=17 ft let the height of the building be,h. h is given by; tan theta=opposite/adjacent theta=80 opposite=h adjacent=75 ft thus tan 80=h/75 h=75 tan 80 h=425.35 ft thus the number of floors will be: 425.35/17 =25.020≈25 floors
8 is positive and 14 negative. You can either draw a number line and help yourself with that or since the negative one is bigger you can do the subtraction 14 - 8 and then change the sign of the answer.