Dan spend half of his allowance going to the movies. He washed the family car and earned eight dollars. What is his weekly allowance if he ended with twelve dollars?

8 dollars

Step-by-step explanation:

if "x" is his weekly allowance:

x-0.5x+8=12

Dan make x dollars, then he spend 0.5x dollars and he earned 8 dollars, and that is 12 dollars.

0.5x=12-8

x=8 dollars