Answer:
a and c
Step-by-step explanation:
Solving The Problem From Eaxh Side Is Easier
Answer:
about 70 years
Step-by-step explanation:
Life expectancy (e) improves by 5.7 years every 10 years, so 5.7/10 = 0.57 years per year. For t years after 2009, it can be modeled by ...
e = 0.57t +80
We want to find when that is 120:
120 = 0.57t +80
40 = 0.57t
40/0.57 = t ≈ 70.2
About 70 years from 2009, humanity may achieve a life expectancy of 120 years.
Answer:
Remember that a triangle's area is bh/2, where
b = base
h = height
So. You start with a triangle of base b and height h, add 2 to the height, and get a triangle of area 82.5.
b(h+2)/2 = 82.5
b(h+2) = 165
What you want to do from here is test the b and h from the choices given, and figure out which b and h satisfy this.
(a) If b=13 and h=15, b(h+2) = 221 nope.
(b) If b=9 and h=11, b(h+2) = 117 nope.
(c) If b=11 and h=13, b(h+2) = 165 that's it!
Step-by-step explanation: