Question 206983
dw=50 or w=50/d
2d+w=20
2d+50/d=20
(2d*d+50)/d=20
(2d^2+50)/d=20
2d^2+50=20d
2d^2-20d+50=0
2(d^2-10d+25)=0
2(d-5)(d-5)=0
d-5=0
d=5 for the depth measurement.
5w=50
w=50/5
w=10 for the width measurement.
Proof:
2*5+10=20
10+10=20
20=10