It took emily 25 min to ride her bicycle to the repair shop in one hour and 15 minutes to walk back home. if emily her bicycle to the repair shop in one hour and 15 minutes to walk back home. if emily can ride her bicycle 8 km/h faster than she can walk how far is the repair shop from her house?

See https://web2.0calc.com/questions/help_62607.

9x

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places