This is a quadratic function:
f(x)=ax²+bx+c
We have three points:
(0 , 77.6)
(5 , 78)
(10 , 78.6)
Then, we make the function wiht these points:
(0 , 77.6)
x=0
f(x)=77.6
a(0)²+b(0)+c=77.6
c=77.6
(5 , 78)
a(5)²+b(5)+77.6=78
25a+5b=78-77.6
25a+5b=0.4 (1)
(10 , 78.6)
a(10)²+b(10)+77.6=78.6
100a+10b=78.6-77.6
100a+10b=1 (2)
With the equations (1) and (2) we have a system of equations:
100a+10b=1
25a + 5b=0.4
We solve this system of equations by method of elimination.
100a+10b=1
-4(25a+5b=0.4)
-----------------------------
-10b=-0.6 ⇒ b=-0.6/-10=0.06
100a+10b=1
-2(25a+5b=0.4)
----------------------------
50a = 0.2 ⇒ a=0.2/50=0.004
We have a, b and c:
a=0.004
b=0.06
c=77.6
Therefore, the quadratic funtion is:
f(x)=0.004x²+0.06x+77.6
x=year of the beginning of the interval - 1980
The life expectancy for females born between 1995 and 2000 is when x=1995-1980=15
Therefore:
f(15)=0.004(15)²+0.06(15)+77.6
f(15)=0.004(225)+0.06(15)+77.6
f(15)=79.4
The life expectancy for females born between 2000 and 2005 is when:
x=2000-1980=20
therefore:
f(20)=0.004(20)²+0.06(20)+77.6
f(20)=1.6+1.2+77.6
f(20)=80.4
Answer:
The funtion is:
f(x)=0.004x²+0.06x+77.6
x=year of the beginning of the interval - 1980
The life expectancy for females born between 1995 and 2000 is 79.4 years.
The life expectancy for females born between 2000 and 2005 is 80.4 years.
The correct answer is c, 370
Answer:
12 in
Step-by-step explanation:
i don't know, you didn't show me the picture.
The correct answer is 2y-6 let me know if you want to know how I got that
If you sketch the man and the building on paper, you'll have a
right triangle. The right angle is the point where the wall of
the building meets the ground. The height of the building
is one leg of the triangle, the line on the ground from the
building to the man's feet is the other leg, and the line
from his feet to the top of the building is the hypotenuse.
We need to find the angle at his feet, between the hypotenuse
and the leg of the triangle.
Well, the side opposite the angle is the height of the building -- 350ft,
and the side adjacent to the angle is the distance from him to the
building -- 1,000 ft.
The tangent of the angle is (opposite) / (adjacent)
= (350 ft) / (1,000 ft) = 0.350 .
To find the angle, use a book, a slide rule, a Curta, or a calculator
to find the angle whose tangent is 0.350 .
tan⁻¹(0.350) = 19.29° . (rounded)
