Answer:
First option: 
Second option: 
Fourth option: 
Step-by-step explanation:
Rewrite each equation in the form
and then use the Discriminant formula for each equation. This is:

1) For
:

Then:
Since
this equation has no real solutions, but has two complex solutions.
2) For
:

Then:
Since
this equation has no real solutions, but has two complex solutions.
3) For
:

Then:
Since
this equation has one real solution.
4) For
:
Then:
Since
, this equation has no real solutions, but has two complex solutions.
Answer: 9 1/3 minutes
First create an equation with the given information; with x being the commercial time, 30=3x+2, now solve for x. First subtract 2 from each side and get 28=3x and then divide each side by 3 to get 9 and 1/3 minutes.
Answer:
3 x 4 = 12
4 x 5 = 20
5 x 2 = 10
Step-by-step explanation:
3 + 3 + 3 + 3 = 12
3 four times equals 12
This is the same for the others
4 + 4 + 4 + 4 + 4 = 20
Four 5 times equals 20
Answer:
No
Step-by-step explanation:
If the ratios of the corresponding sides are equal then they would be the sides of 2 similar triangles.
Calculate the ratio of corresponding sides.
= 4
= 4
≠ 4
Thus the sides are not the corresponding sides of similar triangles.