$\bigg(a + \frac{1}{a} \bigg)^{2} = {a}^{2} + \frac{1}{ {a}^{2} } + 2 \times a \times \frac{1}{a} \\ \\ \bigg(a + \frac{1}{a} \bigg)^{2} = 11 + 2 \\ \\ \bigg(a + \frac{1}{a} \bigg)^{2} = 13 \\ \\ \bigg(a + \frac{1}{a} \bigg) = \pm \sqrt{13}$

5 0

3 years ago

A figure is created by using four semicircles and a rectangle. which is closest to the area of the figure?

Katena32 [7]

Step-by-step explanation:

area of rrctangle:

12×8= 96cm²

now if rectangle dissapears and then we "glue" what's left, we gonna get two circles

area of circle which gas diameter of 12cm( so radius will be 6cm)will be

πr²=36π≈113.04

another circles radius is 4cm,so area is:

16π≈50.25

sum of all areas: S≈96+113.04+50.25≈259.28cm2

7 0

3 years ago

A circle has a diameter of 20 inches and a central angle AOB that measures 160°. What is the length of the intercepted arc AB? U

juin [17]

Calculate the circumference of the full circle:

circumference = PI x diameter = 3.14 x 20 = 62.8 inches
the arc length is 160 degrees of the full circle

divide 160 by 360 (full circle) and multiply by the circumference:

160/360 x 62.8 = 27.9 inches

5 0

3 years ago