6. $1,470
7. $7.88
8. $11.12
9. (dont hold me on it) 4.5522581%
Answer:
Plumber: 13 hours
Plumbing service: 10
Step-by-step explanation:
What you have to find is LCM(least common multiple in order to find the lcm all you have to do is list all the multiples and find their common multiple.
With the facts you got here, you can make the following equation:
x*(x+2)=24
x^2+2x=24
x^2+2x-24=0
Then you can use the following formula (which you might have seen before):
x = (-b +/- sqrt(b^2-4ac))/2a
where
ax^2+bx+c=0
(-2 +/- sqrt(4+96))/2
(-2 +/- 10)/2
x_1 = 4
x_2 = -6
Just find the slope between the points
basically find (f(10)-f(7))/(10-7)
f(7)=7^2-3(7)-4=49-21-4=24
f(10)=10^2-3(10)-4=100-30-4=66
slope=(66-24)/(10-7)=42/3=14
average rate of change is 14
1 mile= 5280 feet
1/5280= 4.25/x This is a proportion.
5280 * 4.25= 22440
22440/1= 22440
4 1/4 miles= 22440 feet
Hope this helps! :D