Example 1
Evaluate -3x + 4 for x = -2.
Example 2
Evaluate 
for x = 10.
Example 3
Evaluate 4x2 for x = -1.
Example 4
Evaluate 5y – 3y2 for y = -2.
Example 5
Evaluate z3 – 18 + z for z = -2.
Example 6
Evaluate 4xyz + x + y – z for x = 2, y = 3, and z = 5.
Example 7
Evaluate b2 – 4ac for a = 1, b = 3 and c = -2.