You can add a lot of numbers (or so I think). One number I think you can add is 31.
Answer:
The equation of line with given points is 2Y - X - 5 = 0
Step-by-step explanation:
Given points are ( - 3 , 1) and (9 , 7)
Equation of line is y = mx +c
where m is the slop of line
Now m = 
Or, m = 
so, slop = 
∴ slop = 
Now the equation of line with points ( -3 , 1) and slop m is :
Y - y1 = m ( X - x1)
Or, Y - 1 =
(X + 3)
Or, 2Y - X - 5 = 0
Hence The equation of line with given points is 2Y - X - 5 = 0 Answer
Slope of AB=(2-3)/(1+1)=-1/2; AC=(-1-3)/(-3+1)=-4/-2=2; BC=(-1-2)/(-3-1)=-3/-4=3/4.
The product of two sides that are perpendicular is -1. Slopes of AB and AC are perpendicular so angle A is a right angle. ABC is a right-angled triangle.
║a+9║/7=5
you multiply 7 on both sides which cancel out 7.
now it ║a=9║=35
and now it would be a+9=35 and a+9=-35 then solve it.
35-9 and 9-(-35)= 26 and -44
hope this helped!