Answer:
Hi there, you can use Pitagoras relationship to solve this up (Without using any other "tool".
Point A is located wheter in (-6,8) or could be located in (-6,8)
Step-by-step explanation:
Point A is 10 units away from the origin, and its x coordinate is -6, using this information, you can draw a triangle from 0 to -6 (the basis) and using 10 as the hypotenuse, so, you have this equation:

solving for Y variable, you have this
y=±
Note the combined sing ±, meaning that y=8 is a valid answer and that y= -8 is also a valid answer.
Hope It helps