The length of the rectangle is 3 m longer than its width. If the length is reduced by 2 m
The length of the rectangle is 3 m longer than its width. If the length is reduced by 2 m, and the width is increased by 4 m, then the area of the rectangle will increase by 8 m ^ 2. Find the original length and width of the rectangle.
Let’s take the length of the rectangle as x and the width as y.
1. Based on the condition, we compose the equations:
1) x = y + 3,
2) x y + 8 = (x – 2) (y + 4).
2. Simplify the 2nd equation:
x y + 8 = x y + 4 x – 2 y – 8,
x y – x y – 4 x + 2 y = -8 – 8,
– 4 x + 2 y = -16.
3. Substitute the value of x from the 1st equation and find y:
-4 (y + 3) + 2 y = -16,
-4 y – 12 + 2 y = -16,
-2 y = -16 + 12,
-2 y = -4,
y = -4: (-2),
y = 2 m – width.
4. Find the length value, use the 1st equation:
x = y + 3,
x = 2 + 3 = 5 m.
Answer: initial values: length – 5 m, width – 2 m.