Answer:
The area of a rectangle is given by the formula:
area = length * breadth
In this case, the length of the rectangle is (x+2) cm and the breadth is (x) cm, so the area is:
area = (x+2) cm * (x) cm
= x^2 + 2x cm^2
We know that the area of the rectangle is 15 cm^2, so we can set up the following equation:
x^2 + 2x cm^2 = 15 cm^2
We can solve for x by using the quadratic formula:
x = (-2 +/- sqrt(4 - 41(-15))) / (2*1)
= (-2 +/- sqrt(64)) / 2
= (-2 +/- 8) / 2
= (-4, 2)
We have two solutions for x, so we need to consider both of them to find the dimensions of the rectangle.
If x=-4, then the length of the rectangle is (x+2) cm = (-4+2) cm = (-2) cm and the breadth is (x) cm = (-4) cm. Since the length and breadth of a rectangle must both be positive, this solution is not valid.
If x=2, then the length of the rectangle is (x+2) cm = (2+2) cm = 4 cm and the breadth is (x) cm = 2 cm. These dimensions give us a valid rectangle with an area of 15 cm^2.
The perimeter of the rectangle is the sum of all four sides, so the perimeter is 2 cm + 2 cm + 4 cm + 4 cm = 12 cm.
Therefore, the value of x that gives us a rectangle with an area of 15 cm^2 and a perimeter of 12 cm is x=2.