a jumbo tablet in the shape of a rectangle has a perimeter of 50 inches. The tablet is 7 inches less wide than it is long. find the length and width of the tablet. help plzz

in rectangles, opposite sides are equal.
lets name the length as x
as stated in the question, width is 7 less than the length 
therefore length is --> x-7
perimeter = 2*(length) + 2(width)
substituting length and width 
perimeter = 2x +2(x-7)
as the perimeter given is 50 inches
70 = 2x + 2x - 14
4x = 84
x = 21 inches 
length of tablet - 21 inches 
width of tablet - 14 inches