The width of the rectangle is 23 cm. How much will the area of this rectangle increase if its length is increased by 3 cm?

Let the value of the length of the rectangle be x cm. Since the area of the rectangle is equal to the product of the length by the width S = a * b, substituting the values of the sides 23 cm and x cm, we find the value of the area: S = 23 * x = 23x. If the length of the rectangle is increased by 3 cm, then the length will be equal to x + 3 cm.Let’s find the area of a rectangle with sides of 23 cm and x + 3 cm.The value of the area is S = 23 * (x + 3) = 23 * x + 23 * 3 = 23x + 69 cm.We find out how much the area of the rectangle will increase if its length is increased by 3 cm: 23x + 69 – 23x = 69 cm.
Answer: 69 cm.