Answer:
It is Commutative
Step-by-step explanation:
An operation ∆ is said to be Commutative if a∆b=b∆a ∀ a,b ∈ ℝ.
Given the operation ∆ defined by:
a∆b=a X b
a∆b=
=3
Similarly, for the right hand side.
Therefore:
b∆a=
=3
These are the two ways of solving this problem and we have in fact shown that the operation is commutative as:
a∆b=b∆a=3
{\text{Direction of parabola depends on the sign of quadratic coefficient of a }} \hfill \\
{\text{quadratic equation}}. \hfill \\
{\text{For given quadratic equation}}. \hfill \\
a{x^2} + bx + c = 0 \hfill \\
{\text{The parabola is in the upward direction if }}a{\text{ }} > {\text{ }}0{\text{ and in downward direction if }}a < 0 \hfill \\
{\text{Here, the equation of given parabola is }} \hfill \\
{x^2} - 6x + 8 = y \hfill \\
\Rightarrow y = \left( {{x^2} - 6x + 9} \right) - 9 + 8 \hfill \\
\Rightarrow y = {\left( {x - 3} \right)^2} - 1. \hfill \\
{\text{Thus, the parabola is in the upward direction}} \hfill \\
Due to the inclination of the
terrestrial axis, the day has different duration in several points of the
planet, which also depends on the time of year. However, this duration remains the same throughout the year in the Equator,
which is known as the imaginary line that divides the planet in two
hemispheres: Northern Hemisphere and Southern Hemisphere.
Answer:
36 miles
Step-by-step explanation:
(Imagine a huge triangle on a perfectly open space-- not with streets or houses or cornfields.)
The dimensions of the two sides given are multiples of a classic Pythagorean Triple: 3, 4, 5. 
9 is 3x3, 12 is 3x4 so the remaining side would be 3x5 15
Add those 3 sides to get the total distance, 36 miles.
