How do you convert a whole number to a percentage?

Find the domain of the function  [tex]f(x) = \sqrt{3x - 7} [/tex]in interval form, the domain of f is what? in advance.

With alll of except for the 2 that i did already

Aright triangle has an area of 21 m2. the dimensions of the triangle are increased by a scale factor of 4. what is the area of the new triangle