x y = - 48
x - y = 19
y = x - 19
x ( x - 19 ) = - 48
x² - 19 x + 48 = 0
x² - 3 x - 16 x + 48 = 0
x ( x - 3 ) - 16 ( x - 3 ) = 0
( x - 3 ) ( x - 16 ) = 0
Factors : x = 16, and y = -3
( 16 * ( -3 ) = -48; 16 - (-3 ) = 16 + 3 = 19 )
Sum of the factors : 16 + ( -3 ) = 16 - 3 = 13
Answer : C ) 13.