The length of the square is p and the width is p so the perimeter (adding all 4 sides) is p+p+p+p = 4p.
The perimeter of the rectangle is 10 more than the square. So for it p = 10+4p.
The perimeter of the rectangle is also equal to adding all 4 sides which is b inches.
10 + 4p = b
Hope that helps!
answer: f true