Answer:
( -1 , 26)
Step-by-step explanation:
So since you need to find the other endpoint, you would follow these steps:
1.) 
2.) 8 = 9 + x ( you just multiplied the 2 to the 4 to get 8)
3.) -1 = x (just solve it like a regular equation, so just subtract 9 on both sides to get rid of it and that leaves you with -1 = x)
You took the x values of both points and put them in the equation.
And its the same for y
1.) 
2.) 16 = -10 + y
3.) 26 = y (you added the 10 on both sides because the 10 was negative and that took the 10 out and so it left you with 26 = y)
There are 200 students in the group.
To find this, you divide 70 by 0.35 (35%). This will give you 200. To check this, multiply 200 by 0.35 and you will get 70. Thus making 200 the answer.
I hope this helps!
First term ,a=4 , common difference =4-7=-3, n =50
sum of first 50terms= (50/2)[2×4+(50-1)(-3)]
=25×[8+49]×-3
=25×57×-3
=25× -171
= -42925
derivation of the formula for the sum of n terms
Progression, S
S=a1+a2+a3+a4+...+an
S=a1+(a1+d)+(a1+2d)+(a1+3d)+...+[a1+(n−1)d] → Equation (1)
S=an+an−1+an−2+an−3+...+a1
S=an+(an−d)+(an−2d)+(an−3d)+...+[an−(n−1)d] → Equation (2)
Add Equations (1) and (2)
2S=(a1+an)+(a1+an)+(a1+an)+(a1+an)+...+(a1+an)
2S=n(a1+an)
S=n/2(a1+an)
Substitute an = a1 + (n - 1)d to the above equation, we have
S=n/2{a1+[a1+(n−1)d]}
S=n/2[2a1+(n−1)d]
Let's assume you have supplement angle

Now when you talk about multiplication you can simply say...

And that will give you the answer.
In 5 years it grew 6 mill (181-175=6). Formula: 6(20/5)+181=X. multiply 6 by 4 (the number of five years in twenty years): 24. 24+181=205 million :)