We are given the perimeter of the given figure = 6x.
We need to find the length of the indicated side in the given figure.
We are given sides :
Side 1: x+3.
Side 2: 2x+4.
Side 3 : ?
Perimeter is the sum of all sides of a given figure.
Let us assume unknown sides is k.
Therefore,
Perimeter = Side 1 + Side 2 + Side 3 .
x+3 + 2x+4 + k = 6x.
Let us solve it for k now.
Combining like terms.
3x +7 +k = 6x
Subtracting 3x from both sides, we get
3x-3x +7 +k = 6x-3x
7 + k = 3x.
Subtracting 7 from both sides, we get
7 -7+ k = 3x-7.
k = 3x -7.
Therefore, the length of the indicated side is 3x -7.