35/11 = 3.18.....
This means that out of 35 rounds only 3 of them were free because every 11 rounds 1 is free.
so 35-3=32
You purchased 32 rounds.
Please mark brainliest. This was kind of a confusing question at first.
Hi,
We know that:
a² -- b² = (a -- b)(a + b).
With a = x, and b = 4, we have:
x² -- 16 = x² -- 4² = (x -- 4)(x + 4).
As simple as that. Have you understood ?
Green eyes.