What does it mean to get 150% salary raise

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.

What is the value of x in the equation 2(x-4) = 4(2x + 1)?

If a || b and e || f , what if the value of y ?