Answer:
40
Step-by-step explanation:
The number after 39, or 39 plus one, is 40.
Well, the length of the shoe box is 20 centimeters and the width is 10. So, 20-10=10 centimeters and sense there's 10 millimeters in a centimeter, you take 10x10= 100 millimeters longer.
-1x=13+9y
(13+9y)+7y=-19
13+16y=-19
16y=-6
•Y=6/16
-1x-(9•6/16)=13
-1x-3.375=13
-1x=16.375
•X=-16.375
0.05x=20
-------- -------
0.05 0.05
×=400