SOLUTION: A labourer built 15 m of stone wall. If she had built 2 m less each day, it would have taken her 2 days longer. How many metres did she build each day, working at her usual rate?

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: A labourer built 15 m of stone wall. If she had built 2 m less each day, it would have taken her 2 days longer. How many metres did she build each day, working at her usual rate?       Log On


   

Question 1170220: A labourer built 15 m of stone wall. If she had built 2 m less each day, it would have taken her 2 days longer. How many metres did she build each day, working at her usual rate?

Answer by ikleyn(52777) About Me  (Show Source):
You can put this solution on YOUR website!
.

Let x be the unknown value under the question.


Then from the condition you have this equation


    15%2F%28x-2%29 - 15%2Fx = 2   days.


You can solve it formally, reducing the equation to the standard quadratic form.


But the solution is seen immediately  x= 5  meters.


CHECK.  15%2F%285-2%29 - 15%2F5 = 15%2F3 - 15%2F5 = 5 - 3 - 2 days.   ! Correct !

Solved   //   mentally.