The perimeter of the rectangle is 48 cm. If one side of it is doubled and the other is reduced by 6 cm
The perimeter of the rectangle is 48 cm. If one side of it is doubled and the other is reduced by 6 cm, then the perimeter of the new rectangle will be 64 cm. Find the sides of this rectangle.
1. Let’s denote the sides of the rectangle by a and b. Then the perimeter will be 2 * (a + b). By condition, the perimeter is 48 cm.We get:
2 * (a + b) = 48;
a + b = 48/2;
a + b = 24.
a = 24 – b.
2. Increase side a by 2 times, and decrease side b by 6. The perimeter of this rectangle will be 2 * (2a + (b – 6)). By condition, this perimeter is 64 cm.We get:
2 * (2a + (b – 6)) = 64;
2a + (b – 6) = 64/2;
2a + b – 6 = 32;
2a + b = 32 + 6;
2a + b = 38;
3. Substitute into the equation of item 2 the value a from item 1:
2 * (24 – b) + b = 38;
48 – 2b + b = 38;
-b = 38 – 48;
-b = -10;
b = 10 cm.
4. Find side a:
a = 24 – b;
a = 24 – 10;
a = 14.
Answer: the sides of a given rectangle are 10 and 14 cm.