Answer:

Step-by-step explanation:
Quadratic Formula: 
√-1 is imaginary number i
Step 1: Define
y = -3x² + 4.5x - 20
a = -3
b = 4.5
c = -20
Step 2: Substitute and Evaluate







Answer:
Step-by-step explanation:
12 multiplied by 9 is 108. That gives us the square. The triangle base is 9. The height is 7. 7 multiplied by 9 is 63. 63 divided by 2 is 31.5. 108 add 31.5 is 139.5 cm squared.
You subtract 11 from 19 and then the answer is 8