Please Help Me!! Its for a math test ;-;
Thank you :>

I’m stuck on this i don’t understand.

To finance her community college education, sarah takes out a loan for $2900. after a year sarah decides to pay off the interest, which is 4% of $2900. how much will she pay

Sanjay solved the equation below. which property did he use to determine that 7x+42=42 is equivalent to 7(x+6)=42 7x+42=42 7x=0 x=0