Answer:
width = 15 inches
length = 30 inches
Step-by-step explanation:
[tex]\sf \boxed{\text{\bf Perimeter of rectangle =2*length + 2*width}}[/tex]
Let width = x inches
Length = 2*x = 2x inches
Perimeter = 90 inches
2 *length + 2* width = 90
2*2x + 2*x = 90
4x + 2x = 90
Combine like terms,
6x = 90
Divide both sides by 6,
x = 90/6
x = 15
Dimensions:
Width = 15 inches
Length = 2*15 = 30 inches.