16-a²= (4-a)(4+a)a²-25b²= (a-5b)(a+5b)49-121t²= (7-11t)(7+11t)t²-p⁴= (t-p²)(t+p²)625-a²= (25-a)(25+a)144-81t²= (12-9t)(12+9t)x⁴y⁴-1= (x²y²+1)(x²y²-1)(a+k)²-(a-k)²= (a+k+a-k)(a+k-a+k) = (2a)(2k) = 4ak25t²-(2z+3t)= (5t-2z)(5t+3t) = (5t-2z)(5t+3t)= 5t-2z4a²-9b²= (2a-3b)(2a+3b)
16-a²= (4-a)(4+a)
a²-25b²= (a-5b)(a+5b)
49-121t²= (7-11t)(7+11t)
t²-p⁴= (t-p²)(t+p²)
625-a²= (25-a)(25+a)
144-81t²= (12-9t)(12+9t)
x⁴y⁴-1= (x²y²+1)(x²y²-1)
(a+k)²-(a-k)²= (a+k+a-k)(a+k-a+k) = (2a)(2k) = 4ak
25t²-(2z+3t)= (5t-2z)(5t+3t) = (5t-2z)(5t+3t)= 5t-2z
4a²-9b²= (2a-3b)(2a+3b)