Original price: discount: 5% sale price: $68.40

So, if the discount was 5%, then the sale prize was equal to 95% of the original prize

so 68.40=0.95*x

we divide both sides by 0.95. Let;s start by multiplying them by 100:

6840=95*x

divide by 5 both sides:

1368=19x
now divide by 19

72=x

so the original prize was 72.

The coordinates of point a right now is (-3,-1) you have to multiply these coordinates by a factor of 2 to get (-6,-2)