Answer:
20
Step-by-step explanation:
Evaluate 3 x^2 - 4 x where x = -2:
3 x^2 - 4 x = 3×(-2)^2 - -2×4
Hint: | Evaluate (-2)^2.
(-2)^2 = 4:
3×4 - 4 (-2)
Hint: | Multiply 3 and 4 together.
3×4 = 12:
12 - 4 (-2)
Hint: | Multiply -4 and -2 together.
-4 (-2) = 8:
8 + 12
Hint: | Evaluate 12 + 8 using long addition.
| 1 |
| 1 | 2
+ | | 8
| 2 | 0:
Answer: 20