The perimeter of a triangle is 20 cm. The lengths of the sides are x, x + 3, and x + 5. What is the length in centimeters of the longest side?

The side of the longest triangle would be 9cm.

First, we need to find x

To do this, we add all 3 sides together to get the perimeter (20) :

x + x + 3 + x + 5 = 20

3x + 8 = 20

We then use this equation to find x :

3x + 8 = 20

(minus 8 on both sides)

3x = 12

(divide by 3 on both sides)

x = 4

Now we have x, we substitute it into the longest side (x + 5)

4 + 5 = 9cm.

when rotating a figure 180 degrees, imagine that you are able to take the figure and turn it clockwise or counterclockwise around a center point. to rotate a figure 180 degrees, you will need to apply the rule (x, y) → (-x, -y). start by using a coordinate grid with coordinates for each vertex of the figure. the center point of the coordinate grid is located at (0, 0), which is what you will rotate the figure around. write down the original coordinates of the shape you are going to rotate. then, apply the rule. for example, coordinate (1, 2) becomes (-1, -2). another example would be, coordinate (-4, -2) becoming (4, 2). after you change each original coordinate to the rotated coordinate, you will draw your new figure.

step-by-step explanation: