What are appropriate ways of write "6 times x"?

For the equations below which statement is true ? -2x=14 6x=-42

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

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.