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.
Dang elementary school homework is hard
Answer:
i wanna say 3
Step-by-step explanation:
i believe its 3 because if you add that 1/2 to the 3/4 you could have a 3 and 3 divided by 9 is 3 (forgive me if incorrect)
Y = x² - 8x + 29
y = (x² -8x +4²) + 29 -4² . . . . add and subtract the square of half the x-coefficient
y = (x -4)² + 13 . . . . . . . . . . . . simplify
The appropriate choice is
C. y = (x - 4)² + 13