If x = -1/2, y = 1/4 and z = 0, find the value of the given expressions
(a) 8z + 2x -y
(b) z – y + 3x
(a) 8z + 2x - y = 8 × 0 + 2(-1/2) - 1/4
= 0 - 1 - 1/4
= (-1 × 4 - 1 × 1)/4
= (-4 - 1)/4 = -5/4
(b) z - y + 3x = 0 - 1/4 + 3(-1/2)
= 0 - 1/4 - 3/2
= (-1 × 1)/(4 × 1) - (3 × 2)/(2 × 2)
= (-1 - 6)/4 = -7/4