It is given in the question that,
A sailboat has a triangular sail with an area of 30 square feet. the height of the sail is 7 feet more than the length of the base of the sail.
Let the length of the base be x, so height is

And formula of area of triangle is

Substituting the values of Area, base and height,

Multiplying both sides by 2


So the base is 5 feet and the height is 12 feet.