What is the best approximation for the area of this figure?

This area can be seen as a semicircle plus a triangle. So, we will find the area of each figure and then add both to get the total area.

The area of a triangle is given by the following formula:

  (1)

Where is the base and   is the height.

  (2)

Now we are going to find the area of the cemicircle, which is the half of the area of a circle:

  (3)

Where is the radius, in order to find it we have to calculate the diameter of this semicircle first, and we will do it as follows:

We know the points of the ends of the diameter, which are:

and

We have to use the Pithagorean theorem to calculate the distance between both points (taking into account the x-component and the y-component of each one)

>>>>This is the diameter of the semicircle

Then, the radius is:

Now we can use the formula written in equation (3):

  (4)

Adding (2) and (4):

>>>>This is the answer  

75 tickets have been sold so far.

step-by-step explanation:

in this question it is clearly mentioned that 45 children's tickets have been sold and this number is 60% of the total tickets sold.

now let's assume the total number of tickets sold be x.

then 60% of x = 45

⇒

⇒ x(.6) = 45

by dividing with .6 on both the sides of the equation

⇒ x = 75

therefore 75 tickets have been sold so far.

if x decreases by 4 then y increases by 10

step-by-step explanation: