## Algebra 1

We use the formula for the difference of squares to apply to this question. The difference of squares formula is: $(a-b) (a+b) = a^{2} - b^{2}$ = $16x^{2}$ - 121 *** Take the square root of $16x^{2}$ which is 9r. Becuase 4x × 4x= $16x^{2}$ *** Take the square root of 121 which is 11. Becuase 11 × 11= 121 = $(4x)^{2}−11^{2}$ In the given formula let 4x represents a and 11 represents b. $(4x)^{2}−11^{2}$ = (4x+11)(4x-11)