Help! Write and evaluate an expression for the problem.

You buy a hat for $12 and give the cashier a $20 bill. How much change do you receive?

An expression is:

The change received is:$​

The change received is $8.00

Step-by-step explanation:

20-12=8

geometry: triangles

solvers

lessons

answers archive

call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584