# How do you factor 64x² - 81y²?

You can use the notable: ${a}^{2} - {b}^{2} = \left(a - b\right) \left(a + b\right)$
$64 {x}^{2} - 81 {y}^{2} = \left(8 x - 9 y\right) \left(8 x + 9 y\right)$