Answer:
Step-by-step explanation:
(9x-1)^-1/2 - (x+2)(9x-1)^-1/2
= (9x-1)^-1/2( 1 - (x + 2))
= (9x-1)^-1/2(-1 - x)
= -(x + 1)(9x-1)^-1/2
= -(x + 1) / (9x-1)^1/2
Answer:
24-3=21 , 36-4=32 , 3+4=7 , 7 x 5 , which equals 35
Step-by-step explanation:
Answer:
$31.25
Step-by-step explanation:
Let's set up an equation.
$220. 28 - total
$126.53 - cost for parts
3 - # of hours
? - price per hour
3h + $126.53 = $220.28
Subtract $126.53 from both sides.
3h = $93.75
Divide by 3.
h = $31.25
The mechanic charges $31.25 per hour for labor.
Hope that helps.
Answer:
It takes 75 years for the investment to quadruple in value
Step-by-step explanation:
Simple Interest
This is a simple interest problem.
The simple interest formula is given by:

In which E is the amount of interest earned, P is the principal(the initial amount of money), I is the interest rate(yearly, as a decimal) and t is the time.
After t years, the total amount of money is:

In this question:
4% simple interest per year, so I = 0.04.
Quadruple:
t when T = 4P.
The interest earned is:



Now we find the time.





It takes 75 years for the investment to quadruple in value