Răspuns: Ai mai jos rezolvarea
Explicație pas cu pas:
Buna!
Aplicam formule de calcul prescurtat
[tex]\color {cc0000}\Large \boxed{ \bf (a + b) \cdot(a - b) = {a}^{2} - {b}^{2} }[/tex]
[tex]\it~~[/tex]
[tex]\large \bf (4x + 5) \cdot(4x -5) = (4x)^{2} - {5}^{2} = \boxed{\bf 16x^{2} - 25 }[/tex]
[tex]\it~~~[/tex]
[tex]\large \bf (y - 5) \cdot(y +5) = y^{2} - {5}^{2} = \boxed{\bf y^{2} - 25 }[/tex]
[tex]\it~~~[/tex]
[tex]\large \bf (x -3y) \cdot(x +3y) = x^{2} - (3y)^{2} = \boxed{\bf x^{2} - 9y^{2} }[/tex]
==pav38==
