(5m-1)²-(5m-3)(5m+3). Решите пожлста

Question

(5m-1)²-(5m-3)(5m+3). Решите пожлста

Answer 1

25m^2 - 10m + 1 - 25m^2 - 15m + 15m + 9 = -10m + 10
10m = 10
m=1

Answer 2

(5m-1)^2-(5m-3)(5m+3)=((5m)^2-10m+1)-(25m^2-15m+15m-9)=
25m^2-10m+1-25m^2+15m-15m+9=-10m+10