Question

If x = 7, y = -6 and z = -2, find the value of 

i. (x + y) + z 

ii. x + (y + z) 

iii. xyz 

iv. (x + y)z 

v. xy + xz

Answer 1

i. (x + y) + z = (7 + -6) + -2 = 1 – 2 = -1

ii. x + (y + z) = 7 + (-6 + -2)

= 7 – 8 = -1

iii. xyz = 7 × -6 × -2 = 84

iv. (x + y)z = (7 + -6) × -2

= 1 × -2 = -2

v. xy + xz = (7 × -6) + (7 × -2)

= -42 – 14

= -56