My tomato leaves are starting to wither and get yellow patches on the leaves

[BenGman]

I've heard what this is, but im not exactly how i'm supposed to treat it. The leaves on the top of my plant are starting to curl inward and like i said, have yellow splotches on the leaves. What do i do? Thanks

[TQ]

Yellow spots indicate leaf disease. While you're spraying for mildew on your squash, apply some fungicide on your tomatoes, too.