The area of the room must equal the sum of the areas of the tiles...
20*30=n(2*3)
600=6n
n=100
So 100 tiles are needed.
For number 15 and 16, you just have to find the absolute difference between the two points along the calibration of the protractor.
15. ∠BXC = |B - C| = |140° - 110°| = 30°
16. ∠BXE = |B - E| = |140° - 30°| = 110°
For numbers 20 and 21, apply the Angle Addition Postulate. This is when you add the individual interior angles to equate to the total angle.
20. ∠PQS = ∠PQR + ∠RQS
112° = 72°+ 10x°
x = 4
21. ∠KLM = ∠KLN + ∠NLM
135° = 47°+ 16y°
y = 5.5
The steps are shown here.
1) Factoring
2) Completing the square
3) Quadratic Formula
4) Graphing
So basically the answer would either be 5 or -5.
Just divided 1.3/100 and it gives you 0.013
