Yoo 9th grade math please help me out My grade is slowly slipping

Could somebody me with this radical simplification?

Right triangle xyz has a right angle at vertex y and a hypotenuse that measures 24 cm. angle zxy measures 70º. what is the length of line segment xy? round to the nearest tenth. 8.2 cm 8.7 cm 22.6 m 25.5 cm

Andy has $310 in his account. each week, w, he withdraws $30 for his expenses. which expression could be used if he wanted to find out how much money he had left after 8 weeks?