In order to prove the triangle is a right angled triangle we need to prove that the slope of the lines CA and BC and AB have any negative reciprocals.Lets find the slopes .
AB=(-1,3), (1,2) slope of AB = 2-3/1-(-1)= -1/2 slope of AB is -1/2
BC = (1,2), (-3,1) slope of BC is 1-2/-3-1= -1/-4 slope of BC is 1/4
Slope of CA =(-3,1)(-1,3) slope of 3-1/-1-(-3)=-2/-2=1
Since the slopes do not have any negative reciprocals so the triangle is not a right angled triangle
A vertical line that passes through (-5,0)
You haven't provided the required roots, but I can tell you how to do this kind of exercises in general.
If the 
coefficient is 1, i.e. the equation is written like 
, then you can say the following about the coefficients b and c:
is the opposite of the sum of the roots
is the multiplication of the roots.
So, for example, if we want an equation whose roots are 4 and -2, we have:
So, the equation is 
If your roots are rational, you can work like this: suppose you want an equation with roots 3/4 and 1/2. You have:
And so the equation is
In order to have integer coefficients, you can multiply both sides of the equation by 8:
The population standard deviation, σ = 1.68, the sample standard deviation, s = 1.95, the sample mean =7.23, and the sample size, n = 39.The test statistics is given by
T=(n - 1) (s / σ)²
= (39 - 1) (1.95 / 1.68)²
= 38 (1.35)= 51.196
