Answer: The length is 510 and the width is 110.
Step-by-step explanation:
To find the area of a rectangle, you will have to add the 2 times the length plus 2 times the width because a rectangle have 4 sides. Two widths and two lengths.
You can now use the formula P= 2l + 2w
were P is the perimeter , l is the length, and w is the width.
the length is 400 more than the width, so we can represent that by the equation, l = w + 400
And now we know that the width is w.
So now we will input the perimeter, length, and into the formula to solve for w.
1240 = 2(w + 400) + 2w
1240 = 2w + 800 + 2w
1240 = 4w + 800
-800 -800
440 = 4w
w = 110
L= 110 + 400
L = 510
Check :
1240 = 2(510) + 2(110)
1240 = 1020 + 220
1240 = 1240