Reason:
The template applies to any quadratic to graph out a parabola. The coefficient for the x^2 term is 'a', and it solely determines whether the parabola opens upward or downward.
If 'a' is negative, then the parabola opens downward. The way to remember this is that 'a' being negative forms a negative frown.
On the other hand if 'a' is positive, then it forms a positive smile, and the parabola opens upward.
In this case, the points are fairly close to a parabola opening downward. This means 'a' is negative and a < 0.
Step-by-step explanation:
To multiply the fractions, like
Multiply the top,
then multiply the bottom.
Try to use a calculator if you aren't arithmetic heavy, but I suggest you to try to remember them because they are going to be helpful for courses like Algebra, Calculus, Statistics, etc.
To divide fractions, like
You take the top number,
Then you flip the bottom number,
Then multiply the two
And that is your answer. Comment if you need more clarification