Answer
Solution is $(1,2,5)$
Work Step by Step
$5x = 5$ Equation $(1)$
$2x+y = 4$ Equation $(2)$
$3x+y-4z = -15$ Equation $(3)$
From Equation $(1)$, we get
$5x = 5$
$x = 1$
Substituting $x$ value in Equation $(2)$
$2x+y = 4$
$2(1)+y = 4$
$2+y = 4$
$y = 4-2$
$y = 2$
Substituting $x$ and $y$ values in Equation $(3)$
$3x+y-4z = -15$
$3(1)+2-4z = -15$
$3+2-4z = -15$
$5-4z = -15$
$-4z = -15-5$
$-4z = -20$
$z= 5$
$x = 1$
$y = 2$
$z = 5$
Solution is $(1,2,5)$