What is the value of the expression below when z, equals, 5z=5?

Question

3, z, squared, plus, z, minus, 4
3z
2
+z−4

Answer 1

When z = 5,

3z^2 + z - 4
= 3(5)^2 + 5 - 4
= 3(25) + 5 - 4
= 75 + 5 - 4
= 80 - 4
= 76

Therefore, 3z^2 + z - 4 equals 76 when z = 5.