Let width = x
let length = 2x
x + 2x = 450
3x = 450
x = 150
width = 150
length = 2x = 2 (150) = 300
In order from left to right:
D, C, A, B
Since the measures of the two angles are in the ratio 8:1, this means the bigger angle's is 8x and the smaller angle is x. Since they are complementary, they add to 90°, so you create the equation 8x+x=90°. This can be simplified to 9x=90°. Then, you divide 90 by 9 to get 10. This means x=10. Next, you replace x with 10 to find the measure of the bigger angle. 8x10=80, so the larger angle is 80°.
3/5 is 60% 3/15 is 20% divide 60% by 20% and you have a 3 hope this helps