You can solve by using Pythagoras theorem.
Let the longest side be c.
a^2 + b^2 = c^2
If this holds, it is a right angle.
But, 3.5^2 + 4.5^2 is not equal to 5.5^2.
To get the answer, divide 1456 by 30
1456 / 30 = 48.53
Because there is leftover coins that cant fit a complete page, they would need one more page.
48 + 1 = 49
Kevin and his dad would need 49 pages to put all thr coins in the album.
The answer is 12^6-10=12^4