He can use his debit card to purchase the bike now. (Not an option)
Triangles ABC and MNO are similar:
1.) same shape-different size
2.) corresponding angles are equal-both triangles are isosceles triangles.
3.) corresponding sides are in the same ratio 12/7.5=8/5=1.6
It changed by $.04 in 4 years.
$.04 / 4 = $.01
The stamp changed by 1 cent/year
-1-7x-6(-7-x)=36
-1-7x+42+6x=36
41-7x+6x=36
41-x=36
-x=36-41
-x=-5
Answer: x=5