In the figure above the perimeter of triangle ABC is 30 cm^2 .Find the length of line AC​

Which of the expressions (on the photo document i inserted) together represent all solutions to the following equation? 8cos(12x)+4=-4 *the answer should be in degrees.* > i would like for someone to explain the process to find the solutions for this.

The product of two negative rational numbers is always zero sometimes zero never zero

Solve the proportion of 16/50=x/156.25