Question 870952
the original dimensions 20 * 23

let the diminished length be x

new dimensions (23-x) & (20-x)

New Area =20*23-120

=340 cm^2

(20-x)(23-x)=340

460-20x-23x+x^2=340

x^2-43x+120=0

x^2-40x-3x+120=0

x(x-40)-3(x-40)=0

(x-40)(x-3)=0

x=3 OR 40

40 is not possible

the width reduced is 3 cm

New dimension 17 by 20 cm