Answer:
Step-by-step explanation:
2) 1320cm squared because you would multiply length x width x height
4) 11.132ft squared because again you multiply length x width x height
brainly should let more people answer the question's
Step-by-step explanation:
Answer:

Step-by-step explanation:
a=3, b=-15, c=20
Discriminant can be calculated as


The roots are imaginary
The solution is


The roots are not real i.e these are imaginary
a=3, b=5, c=-8
Discriminant can be calculated as


The roots are real
By quadratic formula method
The solution is



which are required roots.
I choose this method because I can get the solutions directly by substituting the values in formula, and I don't have to guess the possible solutions.