tolong dikerjakan beserta caranya, terima kasih

Vektor

a tegak lurus b
a.b = 0
-2(3) + x(-1) + 5(2) = 0
-6 - x + 10 = 0
-x + 4 = 0
x = 4

b serah c  --> b = c
(3, -1, 2) =  k(y, 2, x)
3 = ky --> y = 3/k
2 = k x -->k = 2/x = 2/4 = 1/2
y = 3/ (1/2)
y = 6

a. nilai  x = 4 ,  y = 6
b .hasil  a + b - c =
(-2, x, 5) + (3, -1, 2) - (y, -2, x)
= (-2 + 3 -y) , (x -1-2), (5+2+x)
= (1 -y) , (x-3), (7+x)
y = 6, x = 4
= (1-6), (4-3),(7+4)
= -5, 1 , 11