90 points where at least two of the circles intersect.
<h3>Define circle.</h3>
A circle is a closed, two-dimensional object where every point in the plane is equally spaced from a central point. The line of reflection symmetry is formed by all lines that traverse the circle. Additionally, every angle has rotational symmetry around the centre.
Given,
Four distinct circles are drawn in a plane.
Start with two circles; they can only come together in two places. The third circle contacts each of the previous two circles in two spots each, bringing the total number of intersections up to four with the addition of a third circle. The total number of intersections will rise by another 6 when a fourth circle intersects the first three. And the list goes on.
As a result, we get a recognizable, regular pattern: for each additional circle, there are two more intersections overall than in the circle before it.
The total number of intersections can be expressed as the sum because the maximum number of intersections of 10 circles must occur when each circle contacts every other circle in 2 places each.
2 + 4 + 6 + 8 + 10 + 12 + 14 + 16 + 18 = 90.
90 points where at least two of the circles intersect.
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Answer:
Step-by-step explanation:
a. no. 9 x 15 = 135, so if she sells more than 15 necklaces, she'll make a profit
b. 50n > 135 + 4.50n
The Number of boys in the class is: 18
Let's call "g" to the number of girls in the class.
The problem says that there is "w" fewer boys than girls, so we have:
g-w=18
Then, the number of girls in the class is:
g=18+w
Let's call "x" to the total number of studens in the class:
x=g+18
When we substitute g=18+w into x=g+18, we obtain:
x= (18+w)+18
The total number of studens in the class is:
x=w+36
