Enter the x-coordinate of the solution to this system of equations −2x−y=6

8x+3y=−28

x= ?

I have trouble with these kinds of problems so a mini explanation would really help me out :D

Identify the converse of the following conditional: if a point is in the first quadrant, then its coordinates are positive. if the coordinates of a point are not positive, then the point is not in the first quadrant. if the coordinates of a point are positive, then the point is in the first quadrant. if a point is in the first quadrant, then its coordinates are positive. if a point is not in the first quadrant, then the coordinates of the point are not positive.

Given ab and cb are tangents of p, and m =10°. what is the measure of abp?

Anyone? 15m is what percent of 60m; 3m; 30m; 1.5 km?