i have an area 42ft Lx12ftw i need 2 cover material comes in 50sq yard rolls12 ftL how many rolls do i need?

Answer 1

Your space is 42' x 12' = 504 sq.ft. or 56 sq.yds.
The rolls are 50 sq.yd. or 450 sq.ft.
One roll will not be enough, it will run 37.5 ft.
That will leave a 4.5 ft. strip bare.
If you buy a second roll you'll waste 33 ft.

Answer 2

42 x 12 = 504 ft²
If the roll is 12' long then the width is 50/12 = 4'2"

As the length of a roll is the same as the width of the lawn, then a length of 42ft = 42 ÷ 4.2 = 10 rolls.
Edit:..
Sorry, I misread the question... 50 yds² = 450ft².
450/12 = 37.5ft wide per roll.
42 - 37.5 = 4.5ft.
4.5 x 12 = 54ft² more needed = 54 ÷ 9 = 6 yds²
6 ÷ 50 = 0.12
Total needed = 1.12 rolls.

(What a mess I made at first !)

Answer 3

area=42x12=504sq ft
9sq ft=1 sq yd
material is 50 sq yd=450 sq ft=12x length=12x37.5
You will need 504/450 rolls or 1.12 rolls. If you have to buy complete rolls, you will need 2 rolls.
Or if you wanted to figure the number another way, your area is 42 feet long with 12 foot width and your material is 37.5 and 12 foot width. 42/37.5=1.12