The the parabola opens upward it has a minimum and if it opens downward then it has a maximum :)
Answer:
360 ft
Step-by-step explanation:
<h3>Given</h3>
- Area = 57600 ft²
- Length = x
- Width = 4/9x
<h3>Solution</h3>
- A = lw
- x*4/9x = 57600
- 4/9x²= 57600
- x² = 57600*9/4
- x² = 129600
- x = √129600
- x = 360 ft
a)
Let t represents number of years after 1900
so that means for 1900, value of t is 0
We are given point as (0,55)
and it says that life expectancy increases by 0.2
so that means slope,m=0.2
equation of line is y=mt +b
or y=0.2t +b
now we use point (0,55)
55 =0.2(0) +b
55 =0+b
55= b
so b=55
plug it back into the equation,we get
y=0.2t +55
b)
We are given y=73
so we plug it into the equation we got in part a and solve for t
y=0.2t +55
73 =0.2t +55
73-55 =0.2t
18 =0.2t
18/0.2 =t
90 =t
so t=90
This means the birth year =1900+t =1900+90 =1990
Answer:
Unit rate by which the runner completed the marathon is 0.13 miles per minute.
Step-by-step explanation:
A runner competed a marathon of 26.2 miles in 210 minutes.
we can get unit rate by unitary method.
∵ In 210 minutes a runner completes the distance = 26.2 miles
∴ In 1 minute runner will complete the distance = 
= 0.125 miles per minute
≈ 0.13 miles per minute
Therefore, unit rate by which the runner completed the marathon is 0.13 miles per minute.
