I'm not sure how to do this manually but if you plug in 7/12 in a scientific calculator and then press sin -1 you'll get approximately 35.685
The price of the discount is $25 x 0.15 = $3.75
The price of the book with discount is $25 - $3.75 = $21.25
Answer:
x = 30
Step-by-step explanation:
4x + 2x = 180
6x = 180
x = 30