Answer:
Up
Step-by-step explanation:
Y= 1x^2 + 3x + 9
Y= Ax^2 + Bx + C
To determine which way a parabola opens just look at the coefficient (the number) of the x^2 - Always use the coefficient that is beside the x^2
So, if the coefficient A is positive the parabola is opening upward
if the coefficient A is negative the parabola is opening downward
Given:
The sequence is 25, 20, 15, 10, 5.
To find:
The ninth term of the given sequence.
Solution:
We have,
25, 20, 15, 10, 5
It is an AP because the difference between two consecutive terms are same.
Here,
First term (a) = 25
Common difference (d) = 20-25
= -5
The nth terms of an AP is
Where, a is the first term and d is the common difference.
Putting a=25, n=9 and d=-5 to get the 9th term.
Therefore, the ninth term of the given sequence is -15.
