I need the answer. (will give brainliest)

6

Step-by-step explanation:

We can use ratios to solve

15 ft            18ft

=

5ft               x

Using cross products

15x = 5*18

15x = 90

Divide by 15

15x/15 = 90/15

x =6

the ans is 6

Step-by-step explanation:

bcz if u divide 15 by 3 =5 and 12by 3 =4 &18 by 3 =6

b. an equilateral triangle inscribed in a circle

step-by-step explanation:

we are given the figure of two circles having a triangle inside.

now, we know that,

"when a figure is lying inside an another figure, then the outside figure is known as circumscribed figure and the figure lying inside is referred to as the inscribed figure".

as we see that, the circles are containing the triangle completely.

thus, the circles are the circumscribed figures and the triangle is the inscribed figure.

hence, we get, 'an equilateral triangle is inscribed in a circle'.