Answer:
given
n=9
a=1
d=3-1=2
Step-by-step explanation:
now , by formula,
sn = n/2(2a+(n-1)d)
= 9/2(2×1+(9-1)×2)
=9/2×18
=81
$6.50 I guess, because I added $5 and $1.50 and got $6.50
The correct answer is 720. Just turned it in and got a 100. Good luck and hoped this help ya.
Step-by-step explanation:
use the formula: (a+b)³ = a³+3a²b+3ab²+b³
and place the corresponding values.
Answer:
4 ft
7.2 ft
20 ft
Step-by-step explanation:
When the balloon is shot, x = 0.
y = -0.05(0)² + 0.8(0) + 4
y = 4
The balloon reaches the highest point at the vertex of the parabola.
x = -b / 2a
x = -0.8 / (2 × -0.05)
x = 8
y = -0.05(8)² + 0.8(8) + 4
y = 7.2
When the balloon lands, y = 0.
0 = -0.05x² + 0.8x + 4
0 = x² − 16x − 80
0 = (x + 4) (x − 20)
x = -4 or 20
Since x > 0, x = 20.
