Answer:
A perfect square is a whole number that is the square of another whole number.
n*n = N
where n and N are whole numbers.
Now, "a perfect square ends with the same two digits".
This can be really trivial.
For example, if we take the number 10, and we square it, we will have:
10*10 = 100
The last two digits of 100 are zeros, so it ends with the same two digits.
Now, if now we take:
100*100 = 10,000
10,000 is also a perfect square, and the two last digits are zeros again.
So we can see a pattern here, we can go forever with this:
1,000^2 = 1,000,000
10,000^2 = 100,000,000
etc...
So we can find infinite perfect squares that end with the same two digits.
In the problem, the first equation should be represented like this base on the variable given in the problem:
20p + 9t = 44.4
with that equation, the second equation would is given by this formula, in response with the additional number of paperback and textbook
21p + 14t = 51
to get the system equation in getting the mass of each variable, you should subtract the two equation to simplified the formula.
20p + 9t = 44.4
- 21p + 14t = 51
-------------------------
p + 5t = 6.6 // this is the system equation that could be use in getting the mass of each object
I believe it is a triangular prism
3x-5=1
+5 +5
3x=6
3 3
X= 2