Use distributive property:
16. 5k(3 - 4k)
15k - 20k^2
18. 6g^2(g - 8)
6g^3 - 48g^2
20. -2n^2 (5n - 9 + 4n^2)
-10n^3 + 18n^2 - 8n^4
271 rounded is 300, and 425 rounded is 400, so you could estimate the sum by adding 300 and 400, which equals 700.
Before the new kids the ratio of girls to boys is 15:12 because there are 15 girls and 12 boys now you can simplify by dividing 15 by 3 and 12 by 3 to get 5:4 as your simplified ratio. As far as after the new kids. Since there is 1 new girl you do 15+1 to get 16 and there are 3 new boys so you do 12+3 to get 15 now 16:15 is already in simplest form so your answer is:
Before: 15:12 simplified as 5:4
After 16:15
19/20= 0.95
-1/8= -0.125
17/5= 3.4
HOPE THIS HELPS!
y = Acos(Bx) + D;
D = 4, A = 2. Now T = 2π/B = 5π/8, B = 2π/(5π/8) = 16/5
WE get y = 2cos(16/5x) + 4
