Answer: See explanation
Step-by-step explanation:
I think your question should be a rectangle and not a triangle. A triangle has 3 sides and not 2 sides. In order to solve the question, I'm assuming that you wanted to write rectangle.
Note that the perimeter of a rectangle:.= 2(length + breadth)
Let the width be x
Since the length is 1 1/8 cm longer than the width, therefore, the length is 1 1/8 + x.
Therefore, perimeter = 2(1 1/8 + x + x) = 13 1/4
2(1 1/8 + 2x) = 13 1/4
2 2/8 + 4x = 13 1/4
2 1/4 + 4x = 13 1/4
4x = 13 1/4 - 2 1/4
4x = 11
x = 11/4
x = 2 3/4
Therefore, the width is 2 3/4cm
Length = 2 3/4 + 1 1/8
= 2 6/8 + 1 1/8
= 3 7/8cm
