ElectricPavlov

10% off means Paul pays 90% of the original price

.90 * 2600 = $.............    final price

Is your question supposed to read   ( a+b) / (b-a) ?????

Agree with Zenitsu, but I get    56   as final answer .....

y = you

m = 25 + y

f = 25 + y + 3

y * (25+y) ( 25+y + 3)  = 32130

y³ + 53y² +700y -31430 = 0                          y = 17 via wolframalpha

father = 17 + 28 =   45 y/o      as Vanilla found !

The total amount after 7 years will be

     # periods = 7 x 4 = 28       interest per period in decimal form = .08/4 = .02

Future amount =  $ 8270   (  1 + .02)²⁸         

                       When you calculate this amount, subtract the original  $ 8270 to find the interest earned ....

Starts at a low point so let's use the sin function

Amplitude = 5    period = 4 s     (given)

5 sin ( s x )       will give amplitude of 5

period = 4    usual period is 2 pi ...we need to shorten it to 4 s

                            2 pi /s = 4

                             2 pi/4 = s

5 sin(pi/2 x )

Here is the graph:

https://www.desmos.com/calculator/0r1i8yeu2h

Area = length  *  Width

4 544.25   = L * 75.

4544.25 / 75 = length

L = 4544.25/75 = 60.59 mm

Looking for one leg of right triangle

 pythg theorem   hypotenuse^2 = leg1 ^2 + leg2 ^2

                                  9^2 = 5^2 + leg2 ^2

                                 legg 2 = sqrt (9^2 - 5^2) = sqrt 56  =   2 sqrt 14

I am sure you meant     y = a(x-h)^2 + k      where  h,k is the vertex    

10 000 ( 1 - .015)⁵ =  9272.17       CB had the correct answer but had a 2 where a 5 should have been.....