The length of the rectangle is 85 cm. How much the area of the rectangle will decrease if its width is reduced by 5.

Let’s denote by x the width of this rectangular quadrangle, expressed in centimeters.

Let us express the area of ​​this geometric figure in terms of x.

In the initial data for this task, it is reported that the length of this rectangular quadrangle is 8.5 tens of centimeters, therefore, the area S of this geometric figure is:

S = 85x cm².

If the width of this quadrangle is reduced by 5 cm, then the width of the resulting rectangular quadrangle will be x – 5 cm, and the area S1 of this quadrilateral will be equal to:

S1 = 85 * (x – 5) = 85x – 85 * 5 = 85x – 425 = S – 425 cm².

Consequently, the area of ​​the quadrangle will decrease by 425 cm².

Answer: the area will decrease by 425 cm².