How dangerous is it to drive on the road with 3 bad tires and a brand new one?

It's a 2009 Honda Civic

Pretty bad, especially since the 1 good tire will quickly turn bad. If you can't take care of all of them at once, at least have 2 new ones put on the rear wheels of the car.

Very much so. Also when replacing tires always replace them in pairs if you can't afford all four at one. And always place the new ones on the rear.

Why, you ask?

When Buying Two Tires Instead of Four, Placing the New Tires on the Front is DANGEROUS.

When a vehicle's rear wheels lose their grip on the road, the driver's ability to maintain vehicular control is severely compromised because of oversteer (an occurrence that's also called "fishtailing").

Oversteer (and the loss of control it can lead to) "occurs in many rollovers and single vehicle loss-of-control accidents." 2 It is far more difficult to control than understeer, which occurs when a car's front wheels lose grip. The risks associated with oversteer are severe enough that the tires with the better tread (i.e., a pair of new tires) should always be mounted on the vehicle's rear wheels.

As dangerous as the 3 bad tires. Any tire store can tell you and can sell you used tires that still have 60% of Life in them(as they used to be spares or that was the condition of the tires taken off the car when THAT OWNER OPTED for 4 BRAND NEW TIRES. The used tires sit outside in the racks on display and for much less than new you could get better rubber than you got right now to hold you over the winter or until you need to replace all 4. Better that than dying or crashing and getting mangled up and not dying. So you pay because it was YOUR FAULT.
FWD cars have to have all tires replaced, at the same time. Except if you have a brand new tire(is it your spare?), then you need 4 tires. That is the way tire stores are to operate… To maintain their business license. Pairs can be sold to RWD cars(which are getting fewer every year.)
. Or go to the junkyards and spook around yourself and look for some good tires that are either still mounted on a good rim of an identical year car (as the bolt pattern of the rims change.so stick with the same year) unless the junk yard says which other rims fit(specific years of Honda). What you see is what you get for say maybe $20 for tire and rim that is balanced and you checked to see the rim was not bent. Most times they are not.

Dangerous, for me, not at all. But I been driving for over 56 years, have had some very pitiful vehicles. I know my limits, my vehicles' limits, and I know how to compensate so I will be safe.

I don't know you, but you are probably a kid and are dangerous on the road, more so with a unsafe car.

On here? Very dangerous. In reality? It doesn't matter all that much, especially if the roads are dry.

"Honda Civic" Yeah, someone's gonna die.

The make and model of vehicle makes little difference for this question.

What do you classify as "bad" tires? Bald? Damaged? Leaking air? Etc… What is the road condition like?