Respuesta :

SalmonWorldTopper

Step-by-step explanation:

★ Solution :-

[tex]\sf \longmapsto 139^2 - 138^2[/tex]

[tex]\sf \longmapsto a^2 - b^2 = (a + b)(a - b)[/tex]

Here,

  • a = 139
  • b = 138

[tex]\sf \longmapsto 139^2 - 138^2 = (139 + 138)(139 - 138)[/tex]

[tex]\sf \longmapsto (239 + 138)(239 - 138)[/tex]

[tex]\sf \longmapsto (377)(1)[/tex]

[tex]\sf \longmapsto 377[/tex]

Hence solved !!

Melody08

Answer:

277

Step-by-step explanation:

Algebraic Identity: a²-b²=(a-b)(a+b)

Hence,

139²-138²=(139-138)(139+138)

=1×277

=277