I don’t know which one it is I dint get it?

Marco has $38.43 dollars in his checking account. his checking account is linked to his amazon music account so he can buy music. the songs he purchases cost $1.29. part 1: write an expression to describe the amount of money in his checking account in relationship to the number of songs he purchases. part 2: describe what the variable represents in this situation.

In the polynomial below, what number should replace the question mark to produce a difference of squares? x2 + ? x - 36

When 142 is added to a number the result is 64 more times the number my options are 35 37 39 41