The answer should be 64 cars sold at the dealership
Answer:
Diego is 14 years old.
Sister is 19
Step-by-step explanation:
x = Diego's age
<u>x</u><u> </u><u>+</u><u> </u><u>2</u><u>4</u>
2x-9 = 2
First to get rid of the fraction we multiply each side by 2
2(2x-9) = 2((x+24)/2)
4x-18 = x+24
The we isolate x
4x-18 = x+24
<u>-x+18 -x+18</u>
<u>3x</u> = <u>42</u> Now we divide each side 3
3 3
x = 14
So Diego is 14
Now we can solve for his sister. We can use one of the two equations from earlier to do this.
Plug 14 in for x and then solve for his sister
2(14)-9
28-9
19
His sister is 19
The local minimum of function is an argument x for which the first derivative of function g(x) is equal to zero, so:
g'(x)=0
g'(x)=(x^4-5x^2+4)'=4x^3-10x=0
x(4x^2-10)=0
x=0 or 4x^2-10=0
4x^2-10=0 /4
x^2-10/4=0
x^2-5/2=0
[x-sqrt(5/2)][x+sqrt(5/2)]=0
Now we have to check wchich argument gives the minimum value from x=0, x=sqrt(5/2) and x=-sqrt(5/2).
g(0)=4
g(sqrt(5/2))=25/4-5*5/2+4=4-25/4=-9/4
g(-sqrt(5/2))=-9/4
The answer is sqrt(5/2) and -sqrt(5/2).
1000000 + 300,000 + 40,000 + 5,000 + 800 + 20
