It’s 13.4. pythagoras tells us a^2+b^2=c^2. 12 is a. 6 is b. both numbers squared do add up to 180 however sqroot that is 13.4
You need to add a picture in order for others to understand what you are referring to.
<h2>○=> <u>Correct answer</u> :</h2>
Money in Alex's account after 16 years = 
<h3>○=> <u>Steps to derive correct answer</u> :</h3>
Money invested by Alex = £3045
Percentage of compound interest per annum = 2.25%
We know that :

In this case :
Principal = £3045
Rate = 2.25% = 0.0025
Number of times interest is compounded per year = 1
Time = 16 years
Which means :
Money Alex will have in the account after 16 years :


Therefore, the money in Alex's account after 16 years = £4347.11
The image would then be in quadrant 3 because say you "folded" the coordinate plane across the x-axis, then the point attached onto the other side of the plane, the point would be in the 3rd quadrant.