Answer:
x = 31
Step-by-step explanation:
The perimeter is the sum of the equal-length sides:
63 = (x -10) +(x -10) +(x -10)
63 = 3x -30 . . . . . . . . collect terms
21 = x -10 . . . . . . . . . . divide by 3
31 = x . . . . . . . . . . . . . add 10
The width is 6cm
And the length is two times + 3 of the width
6 X 2 + 3 = 15
Add all 4 sides for the perimeter 6+6+15+15=42
The the dimensions are a rectangle that is 6cm wide and 15cm tall
734: 730 and 700.
102: 100 and 100.
483: 480 and 500.
There you go! ^w^