SOLUTION: Mrs. Roza painted the top of a retagular table. The perimeter is 18 feet. The area of the table is 20 square feet. Which of the following could be the length and width of the table

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Question 1071028: Mrs. Roza painted the top of a retagular table. The perimeter is 18 feet. The area of the table is 20 square feet. Which of the following could be the length and width of the tabletop?
a. 2ft, 9ft
b. 10ft, 2ft
c. 4ft, 5ft
d. 9ft, 9ft
I am so confused on how to find the answer
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Find the dimensions from the given perimeter and area.

system%282w%2B2L=18%2CwL=20%29


-
system%28w%2BL=9%2CwL=20%29
L=9-w
-
w%289-w%29=20
-w%5E2%2B9w-20=0
w%5E2-9w%2B20=0
%28w-4%29%28w-5%29=0

The way this situation works, one of the dimensions is 4 feet and the other dimension is 5 feet. (If you were to first find w in terms of L and do the area formula substitution, you would have (L-4)(L-5)=0, so the same thing, same solutions - you might choose length as the bigger dimension.)

Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
Hey, the situation is much simpler.
They do not ask you to solve equations.
They ask you to check if the given options match/satisfy the condition.


For example, it is obvious that the option A) does not work.

B) also gives wrong perimeter.

D) gives wrong perimeter and wrong area.


To check each option, two skills are necessary and sufficient: 

    - to add numbers (to calculate the perimeter - if you know what the perimeter of a rectangle is),   and
    - to multiply numbers (to calculate the area - if you know what the area of a rectangle is).

This assignment is for the first - second grade students . . .