Help!!

Write the formula for the area of a right triangle if two legs are known.
If the first leg of the triangle is x and the length of the second leg is y, the formula for the area of a right triangle is A = ?

Abike shop sells you a bicycle for $63 and a helmet for $21. the total cost is 150% of what the shop spent originally. how much did the shop spend originally? how much profit did the bike shop earn by selling the bicycle and helmet to you ?

Acircle has a circumference of 2 pi cm. which statement about the circumference and area is true? a comparison of the area and circumference is not possible since the area cannot be determined. the numerical values of the circumference and area of the circle are equal. the numerical value of the circumference is greater than the numerical value of the area. the numerical value of the circumference is less than the numerical value of the area.

The longer leg of a 30° 60° 90° triangle is 16 times square root of three how long is a shorter leg