Question

A bicycle shop has bicycles with 2 wheels and tricycles with 3 wheels. They have 15 different cycles for sale. The 15 cycles have 34 wheels. How many bicycles and tricycles does the shop have for sale.

Answer 1

$x-number\ of\ 2\ wheels\ bicycle\\15-x-number\ of\ 3\ wheels\ bicycle\\\\2x+3(15-x)=34\\2x+45-3x=34\\2x-3x=34-45\\-x=-11\\x=11\\\\15-11=4\\\\The\ shop\ have\ 11\ 2\ wheels\ bicycle\ and\ 4\ tricycles$