Respuesta :

Answer:

6x - 1

Step-by-step explanation:

Side 1: 5x - 1

Side 2: 4x + 4

Side 3: Unknown, y

Perimeter: 15x + 2

Perimeter = Side 1 + Side 2 + Side 3

15x + 2 = 5x - 1 + 4x + 4 + y

15x + 2 = 9x + 3 + y

6x - 1 = y

y = 6x - 1

Side 3 = 6x - 1

RELAXING NOICE
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