A, B, and C are points on the circumference of a circle, centre 0. AOB is a diameter of the circle. Prove that angle ACB is 90° You must not use any circle theorems in your proof.

Kindly refer to explanation.

Step-by-step explanation:

Given that:

A,B and C are 3 points on circumference of circle with centre O.

AOB is diameter.

Kindly refer to the attached image.

To prove:

Solution:

Let and .

Construction: Join point  A with centre O.

Considering :

Side AO = OC because both are the radius.

Angles opposite to equal sides in a triangle are equal.

Therefore,

Considering :

Side BO = OC because both are the radius.

Angles opposite to equal sides in a triangle are equal.

Therefore,

...... (1)

Now, in

Using angle sum property of triangle:

By equation (1):

Hence proved.

So each bar contains 6 and she has 20 so 6 times 20=120

pyramid volume=legnth times width times height times 1/3
v=base times height times 1/2
v=1 times 2 times 1/3
v=2/3
volume of 1 pyramid is 2/3 cubic inches

divide 120 by 2/3 to find out how many pyrimds will fit into amount given
120/1 divide by 2/3=120/1 times 3/2=360/2=180

she can make 180 pyramids