Question

Someone plz help me with this

Answer 1

3. The area of a circle is
`image`

This means that the "r" is the radius and in this case it is 5 in.

`\pi (5)^(2) = 78.54`

4. The circumference of a circle is :
`2\pi r`

This means:
`2\pi (5) = 31.42`

5. We know that the two sides are 5 in. and the angle in the center for both triangles is 90 degrees. A triangle is always 180 degrees in total so we can say that the other two angles must add up to 90 degrees and they are equal so; 90/2 = 45 degrees.

This means that the other two angles are 45 degrees each.

We can use some trigonometry to solve for the missing side;

cos(theta) = adjacent/ hypotenuse

hypotenuse = adjacent / (cos(theta)) .... hypotenuse = 5/ (cos(45)) ... hypotenuse = 7.07

Half of that is 3.535

Area of a triangle = bh/2 .... (7.07 * h)/2

sin(45) = opposite /5 .... 5sin(45) = opposite = 3.54

(3.54 * 7.07) / 2 = 12.5