you can cross-multiply to find the answer.

stands for the unknown price of 2 notebooks.
5 notebooks/$4.65 = 2 notebooks/

you multiply 5 and x & 2 and 4.65, so:
5x = (2)(4.65)
5x = 9.30
then, you divide 5 on both sides, to get the x alone, so:
x = 9.30/5
so the answer is $1.86 for 2 notebooks.