Let x- intercept represents time
Let y-intercept represents population
Let 1990 represent initial year
Points are (0,14.2)(10,12.4)
slope m=
=
General linear equation
y= mx+b --------------(i)
here m is slope and b is intercept
plug the 1st point in equation
14.2= -0.018(0) + b
b=14.2
y= 0.018x + 14.2
replace y with p(t) and x with t
p(t) = -0.018t + 14.2
Answer:
The demand equation is: D=-4p+23
Step-by-step explanation:
To get started, we should keep in mind that the market price (p=3) occurs when supply equals demand ,therefore when p=3
S=2(3)+5=11
Thus, when p=3 D=11 and, according to the problem when p=1 D=19.
We already know two points on the demand curve. Great!
The demand equation is linear, so it has form D=bp+c.
The variable b is the slope of the demand linear equation . It can be computed through the formula
. equation 1
Substituting the two points (3,11) and (1,19) on equation 1.
b=-4
Now we can find the value of intercept of the demand equation c trough point-slope form y-y1=b(x-x1).
We can use any of the points. Let's take (3,11) and write in point-slope :
y-11=-4(x-3)
y=-4x+11+12
y=-4x+23
Rewrite the linear equation according our variables D and p
D=-4P+23
Finally we found the demand equation !