A rectangle dimentions. LMNP
Then both diagonals are
LN = 2x + 9
MP = 9x - 5
In a rectangle, both diagonals are equal
LN = MP
2x + 9 = 9x - 5
Now isolate x
2x - 9x = -5 - 9
-7x = -14
x= -14/-7= 2
Now find lengths of rectangle
LN = 2•2 + 9 = 13
MP = 9•2 - 5 = 13