Answer:

Step-by-step explanation:
I am assuming that you mean
.

<em>Brainilest Appreciated.</em>
1. C
2.D
3.A
4.B
Hope this helps!
Answer:
Twice the length of the radius
Step-by-step explanation:
A radius by definition is half of the diameter which means the diameter is twice the radius.
Question is Incomplete, Complete question is given below.
Prove that a triangle with the sides (a − 1) cm, 2√a cm and (a + 1) cm is a right angled triangle.
Answer:
∆ABC is right angled triangle with right angle at B.
Step-by-step explanation:
Given : Triangle having sides (a - 1) cm, 2√a and (a + 1) cm.
We need to prove that triangle is the right angled triangle.
Let the triangle be denoted by Δ ABC with side as;
AB = (a - 1) cm
BC = (2√ a) cm
CA = (a + 1) cm
Hence,
Now We know that

So;


Now;

Also;

Now We know that




[By Pythagoras theorem]

Hence, 
Now In right angled triangle the sum of square of two sides of triangle is equal to square of the third side.
This proves that ∆ABC is right angled triangle with right angle at B.
Point slope form
y-y1=m(x-x1)
slope=m
a point is (x1,y1)
slope=(y2-y1)/(x2-x1)
given
(-6,4) and (2,0)
slope=(0-4)/(2-(-6))=-4/(2+6)=-4/8=-1/2
a point is (-6,4)
x1=-6
y1=4
y-4=-1/2(x+6)
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