Respuesta :

Photon
He just have to do a substraction.

42 = x +23
42 - 23 = x
19 = x
x= 19

That's simple !

Hope this helps !

Photon
Well to find the answer you could subtract 42 and 23 , which equals 19. Then check your work by adding 19+23 which equals 42 . Therefore , 42= 19 + 23