Keywords
quadratic equation, discriminant, complex roots, real roots
we know that
The formula to calculate the <u>roots</u> of the <u>quadratic equation</u> of the form
is equal to

where
The <u>discriminant</u> of the <u>quadratic equation</u> is equal to

if
----> the <u>quadratic equation</u> has two <u>real roots</u>
if
----> the <u>quadratic equation</u> has one <u>real root</u>
if
----> the <u>quadratic equation</u> has two <u>complex roots</u>
in this problem we have that
the <u>discriminant</u> is equal to 
so
the <u>quadratic equation</u> has two <u>complex roots</u>
therefore
the answer is the option A
There are two complex roots
ANSWER
72km/h
EXPLANATION
The average speed of the car can be calculated using the formula:
Average Speed=total distance/ total time taken.
The car covers a distance of 108km in 1½ hours.
We substitute the values into the formula to obtain,


Therefore the average speed of the journey is 72km/h
Answer: { x | 5 < x ≤ 100 } OR { x ∈ ℝ | 5 < x ≤ 100 }
Step-by-step explanation:
{ x | 5 < x ≤ 100 }
This means:
"The set of all x's, such that x is greater than 5 and less than or equal to 100"
Another acceptable way to write this is
{ x ∈ ℝ | 5 < x ≤ 100 }
"x ∈ ℝ" simply means x is an element of all real numbers