Respuesta :

twenty pounds and 69 p
j20182
{unknown number}
shoe
→$X 
sock→$Y

7X+2Y=39------------1
5X+2Y=29------------2

minus the first and the second,then 2Y would disappear
7X-5X=2X , 39-29=10
then you will have 2X=10 ,so X=5
take X=5 in each of the formula , then get Y=2