<PRE><B>Question 233452</B>
x = number of floor plan 1
y = number of floor plan 2


total number of houses = 56 with 1 floor plan per house.


x + y = 56


number of floor plan 2 = 3 * number of floor plan 1


y = number of floor plan 2 so y = 3x


your equations are:


x + y = 56
y = 3x


replace y with 3x in first equation to get:


x + 3x = 56
this becomes:
4x = 56 which becomes:
x = 14

this makes y = 3x = 42


42 + 14 = 56 so number of total floor plans is correct.
x = number of floor plan 1 = 14
y = number of floor plan 2 = 42


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