Question

(9x-4)^2-(7x+5)^2?если x=1,5

Answer 1

формула:(а-б)×2=а×2+2аб+б×2
81$x^{2}$+72х+16-49$x^{2}$-70х-25
32$x^{2}$+2х-9
32×2.25+3-9=66