How do you solve this step by step?

90

Step-by-step explanation:

Evaluate x^2 + 2 x^2 + 3 x^2 + 4 x^2 where x = 3:

x^2 + 2 x^2 + 3 x^2 + 4 x^2 = 3^2 + 2×3^2 + 3×3^2 + 4×3^2

3^2 = 9:

3^2 + 2×9 + 3×3^2 + 4×3^2

3^2 = 9:

3^2 + 2×9 + 3×9 + 4×3^2

3^2 = 9:

3^2 + 2×9 + 3×9 + 4×9

3^2 = 9:

9 + 2×9 + 3×9 + 4×9

2×9 = 18:

9 + 18 + 3×9 + 4×9

3×9 = 27:

9 + 18 + 27 + 4×9

4×9 = 36:

9 + 18 + 27 + 36

| 3 |  

| 3 | 6

| 2 | 7

| 1 | 8

+ | | 9

| 9 | 0:

 90

i do not know the answer i am sorry

24

step-by-step explanation: