The sum of first 20 arithmetic series 
Given:
Arithmetic series for 3rd term is 55
Arithmetic series for 7th term is -98
To find:
The sum of first 20 Arithmetic series
<u>Step by Step Explanation:
</u>
Solution:
Formula for calculating arithmetic series
Arithmetic series=a+(n-1) d
Arithmetic series for 3rd term 

Arithmetic series for 19th term is


Subtracting equation 2 from 1
![\left[a_{19}+18 d=-98\right]+\left[a_{1}+2 d=55\right]](https://tex.z-dn.net/?f=%5Cleft%5Ba_%7B19%7D%2B18%20d%3D-98%5Cright%5D%2B%5Cleft%5Ba_%7B1%7D%2B2%20d%3D55%5Cright%5D)
16d=-98-55
16d=-153

Also we know





First 20 terms of an AP



![a_{20}=[1106 / 16]-[2907 / 16]](https://tex.z-dn.net/?f=a_%7B20%7D%3D%5B1106%20%2F%2016%5D-%5B2907%20%2F%2016%5D)

Sum of 20 Arithmetic series is

Substitute the known values in the above equation we get
![S_{20}=\left[\frac{20\left(\left(\frac{558}{8}\right)+\left(\frac{-1801}{16}\right)\right)}{2}\right]](https://tex.z-dn.net/?f=S_%7B20%7D%3D%5Cleft%5B%5Cfrac%7B20%5Cleft%28%5Cleft%28%5Cfrac%7B558%7D%7B8%7D%5Cright%29%2B%5Cleft%28%5Cfrac%7B-1801%7D%7B16%7D%5Cright%29%5Cright%29%7D%7B2%7D%5Cright%5D)
![S_{20}=\left[\frac{\left.20\left(\frac{1106}{16}\right)+\left(\frac{-1801}{16}\right)\right)}{2}\right]](https://tex.z-dn.net/?f=S_%7B20%7D%3D%5Cleft%5B%5Cfrac%7B%5Cleft.20%5Cleft%28%5Cfrac%7B1106%7D%7B16%7D%5Cright%29%2B%5Cleft%28%5Cfrac%7B-1801%7D%7B16%7D%5Cright%29%5Cright%29%7D%7B2%7D%5Cright%5D)

![S_{20}=5\left[\frac{-695}{16}\right]](https://tex.z-dn.net/?f=S_%7B20%7D%3D5%5Cleft%5B%5Cfrac%7B-695%7D%7B16%7D%5Cright%5D)

Result:
Thus the sum of first 20 terms in an arithmetic series is 
Answer:
if they vary together then y would be 2
Step-by-step explanation:
since they vary together 5 multiplied by 3 is 15 so you would divide 6 by 3 to get 2 the z is irrelevant because it has no relation to x or y
5000
Step-by-step explanation
this is LITERALLY so easy!!!!!!
6300+4100+1500+950=12850
12850-7850=5000
The answer is <span><span><span>6<span>a3</span></span>+<span>22<span>a2</span></span></span>+<span>14a</span></span>−<span>10
My steps:
</span><span><span>(<span><span>3a</span>+5</span>)</span><span>(<span><span><span>2<span>a^2</span></span>+<span>4a</span></span>−2</span>)</span></span><span>=<span><span>(<span><span>3a</span>+5</span>)</span><span>(<span><span><span>2<span>a^2</span></span>+<span>4a</span></span>+<span>−2</span></span>)</span></span></span><span>=<span><span><span><span><span><span><span>(<span>3a</span>)</span><span>(<span>2<span>a^2</span></span>)</span></span>+<span><span>(<span>3a</span>)</span><span>(<span>4a</span>)</span></span></span>+<span><span>(<span>3a</span>)</span><span>(<span>−2</span>)</span></span></span>+<span><span>(5)</span><span>(<span>2<span>a^2</span></span>)</span></span></span>+<span><span>(5)</span><span>(<span>4a</span>)</span></span></span>+<span><span>(5)</span><span>(<span>−2</span>)</span></span></span></span><span>=<span><span><span><span><span><span>6<span>a^3</span></span>+<span>12<span>a^2</span></span></span>−<span>6a</span></span>+<span>10<span>a^2</span></span></span>+<span>20a</span></span>−10</span></span><span>=<span><span><span><span>6<span>a^3</span></span>+<span>22<span>a^2</span></span></span>+<span>14a</span></span>−<span>10</span></span></span>
Answer:
y = -2x + 5
Step-by-step explanation:
y = mx + b,
where m = slope, and b = y-intercept
y = -2x + 5