You can attempt to install these AMD A12-9800E APU drivers. See if they will install, reboot and retest.

* AMD A12-9800E APU drivers

If still no go, try these Windows 10 Touch Screen drivers. See if they will install, reboot and retest.

* NextWindow driver update for NextWindow 1950 UCS Compliant Touch Screen (Windows 10)
* eGalaxTouch Windows 2000/XP/7/8/8.1/10 Touch Screen driver

Same problem.... tryng reinstalling AMD driver as indicated below .. not working yet

Is there any "unknown" device and/or any entry marked with an X, ! or ? in Device Manager? Be sure to look under USB. 

Open Device Manager and expand list under USB. Double-click a root hub and then click its Power Management tab. Uncheck the box "Allow PC to turn off..". Repeat for all USB root hubs. Now expand list under Human Interface Devices in Device Manager and uncheck that same box for any entry that has a Power Management tab.

Exit Device Manager and open the Win 10 Power options screen. Select your currently active power plan. Follow the links to change plan settings and navigate to the Additional Settings page. Disable USB Selective Suspend. Save the change to the power plan, exit and reboot PC.

Does that help?

Non of the suggestions have worked, ive bow tritried multiple versions of the bios and chipset drivers to no avail, and it seems im not the only one with this problem

Hi 

I have same issues, did you solve yours?

Hello. My Inspiron 24 5475 has exactly the same problem. Suddenly, about three months after the purchase, the touchscreen and camera stopped working.
Do not even appear among the devices in the "device management" of windows 10. I tried to re-flash the bios, to install drivers of any kind, to reinstall windows, but nothing has changed. The touchscreen and the camera have inexplicably disappeared.
Has anyone found a solution to make them work again?

...Dell tech support verified to me during a support call on 6\18\2019 that this model PC (at least some of them) had what they called "known problems with the motherboard".  As of now, replacing the motherboard did fix this issue for me. 

A little background.  Previously I had called in several times about this but eventually gave up after replacing the touchscreen twice and camera once had no lasting effect.  The devices would immediately appear/work after replacing them but were gone again after a few weeks.   Every once in a while the touchscreen would make a brief appearance which I tracked using a program called USBDeview that was always running in the background.   

  So when/if you call in, tell them that this is not an software issue/isolated case and somewhere it is documented that these computers were manufactured with a defect that can only be fixed by replacing the motherboard.    

I hope this helps.

Did they send you a motherboard for free because of the defect or are they not taking ownership of it? I need to get my hands on one too @robkleinpeter 

Inspiron 24 5475 All-in-One is no longer sold.

Unless warranty was extended its not likely you would get a new motherboard.

Actually unless you have done clean install and added the OEM chipset drivers its not likely that the motherboard is bad.

I also see no such documentation of motherboard issue.  The chipset and video and audio drivers are not native to windows 10.  This would cause a problem every time there is a feature update to windows.

http://downloads.dell.com/published/pages/inspiron-24-5475-aio.html