Two angles are supplementary the first angle measures 40 degrees what is the measurement of the second angle

Which best explains why this triangle is or is not a right triangle ?

What is the distance between (3,k+1) and (2k,k-1)

: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.