Plz i want to start 9th grade language arts bit i cant untill i catch up on math

Multiply −2x(6x^4−7x^2+x−5) express the answer in standard form. enter your answer in the box.

:malik received a $300 gift card from his grandparents and is using it only to pay for his karate lessons, which cost $30 per month. determine what amount, in dollars, remains on the card after 8 months.

I'm confused on how to solve the triangle. can someone me ?