Thomas, what you have is a VERY rough estimate and will only give you enough info to tell that you need to get a real soil test done.
The pH factors of both water and soil are measured in decimals (tenths) and every decimal is a 100 times factor. So water that tests at pH 7.5 is 500 times more alkaline than neutral water at pH 7.0. Anything measuring "between 8 and 9" is super alkaline and your plants will struggle. You need a more accurate test than that.
If your drinking water coming out of the tap is over pH 8.0 you really should contact your water company unless you are on a well. Our untreated well water here is pH 8.2 and after only a few weeks of irrigating with it, my plants begin to show signs of iron chlorosis (inability to process nutrients because of the high pH ). So if you're irrigating your garden with high pH tap water it's going to cause you some problems.
You can buy a good soil test kit at any garden center for about $12 and it will test 10 samples to decimal accuracy for you.
Or, you can buy them online - here's an example of one for under $7 (plus shipping) that will give you 10 pH tests.
https://www.amazon.com/dp/B0001LEPYA/
Or this one gives you 40 tests for $22 and looks like it will last you for years. If you have a big garden, I'd get this one:
https://www.amazon.com/dp/B003JCMKEK/
