Answer:
a = -29
Step-by-step explanation:

1st step is to multiply -2 on both sides
The precision is 10 inches. This is because the 0 at the end of the number is not considered a significant digit in the form in which the number is written, and hence "80 inches" is to be considered a roundoff from a number which can be from 75-85 inches.
(-6,7) since it’s the x axis you just change the sign of the y and keep x the same
You need to put more explanation into the problem to help you