Answer:
n = -5, 3.
Step-by-step explanation:
n^2 + 2n - 15 = 0
Let's check if we can factor this quadratic:
We need 2 numbers whose product is -15 and whose sum is +2.
There are 2 such numbers and they are +5 and -3, so the factors are:
(n + 5)(n - 3) = 0.
n + 5 = 0 or n - 3 = 0
therefore the zeroes are -5 and 3.
<h3><em>Answer:</em></h3><h3><em></em></h3><h3><em>number of seats in theater = 1035</em></h3><h3><em></em></h3><h3><em>Step-by-step explanation:</em></h3><h3><em></em></h3><h3><em>Given in question as</em></h3><h3><em></em></h3><h3><em>Total number of rows of seat = 30</em></h3><h3><em></em></h3><h3><em>first row contain seat = 20</em></h3><h3><em></em></h3><h3><em>second row contain seat = 21 .. and so on</em></h3><h3><em></em></h3><h3><em>This is in arithmetic progression as 20 , 21 , 22 , 23 ...... so on</em></h3><h3><em></em></h3><h3><em>Then as number of terms N = 30 and first terms = a = 20</em></h3><h3><em></em></h3><h3><em>so we have to find Tn th terms</em></h3><h3><em></em></h3><h3><em>So, Tn th terms = first term + ( N -1 ) × d d= common difference i.e 1</em></h3><h3><em></em></h3><h3><em> Tn th terms = 20 + (30 - 1) × 1</em></h3><h3><em></em></h3><h3><em>Thus, Tn th terms = 49</em></h3><h3><em></em></h3><h3><em>i.e The number of seats in 30th row = 49</em></h3><h3><em></em></h3><h3><em>Now again Total number of seats in theater</em></h3><h3><em></em></h3><h3><em>sum of Nth terms = </em></h3><h3><em></em></h3><h3><em>so = </em></h3><h3><em></em></h3><h3><em> = 15 × 69 = 1035</em></h3><h3><em></em></h3><h3><em>Hence, Total number of seats in theater = 1035 Answer</em></h3>
Answer:
Mean=8.8, Median=8
Step-by-step explanation:
How to find the mean:
First, add all the #'s up. 4+9+12+14+7+7=53
Then divide that by the number or numbers. In this case it is 6.
53/6=8.833... So rounded=8.8
Median:
List numbers lowest to highest
4, 7, 7, 9, 12, 14
Go to the middle number.
Since it is between 7 and 9, it is 7+9=16. 16/2=8
8 is the median
Answer
4x+y=11
Step-by-step explanation: