Somebody help me please

Solve - pv + 40 < 65 for v solve 7w - 3r = 15 for r

Need ! give step by step solutions on how to solve number one [tex]\frac{9-2\sqrt{3} }{12+\sqrt{3} }[/tex] number two [tex]x+4=\sqrt{13x-20}[/tex] number three (domain and range) [tex]f(x)=2\sqrt[3]{x} +1[/tex]

Enter the number of complex zeros for the polynomial function in the box. f(x) = x+ + 5x² +6