How to make a projectile's motion concave upwards?

Its hard to explain as im rusty in algebra, but i got this script where it has a projectile move in a curved slope (from your humanoidrootpart to your mouses position) and it has a negative acceleration (where it concaves down).

local p = game.Players.LocalPlayer
local m = p:GetMouse()
repeat wait() until p.Character
local c = p.Character
local enabled = true
local t = 1;
local hrp = c:WaitForChild("HumanoidRootPart");
local bball = workspace.Hm;

m.Button1Down:Connect(function()
    local g = Vector3.new(0, -game.Workspace.Gravity, 0);
    local x0 = hrp.CFrame * Vector3.new(0, 2, -2)
	local mp = m.Hit.p--+Vector3.new(0,15,0)
    -- calculate the v0 needed to reach mouse.Hit.p
    local v0 = (mp - x0 - 0.5*g*t*t)/1;

    -- have the ball travel that path
    local c = bball:Clone();
	c.Anchored = false
    c.Velocity = v0;
    c.CFrame = CFrame.new(x0);
    c.Parent = game.Workspace;
end)

What i am trying to do though, is make the slope has a postive acceleration, so that the slope's curve concaves upwards instead, starting as a decreasing slope and ending as an increasing slope when it reaches the destination.. Kinda like this: https://gyazo.com/48e64596375a2505968596c03583230c?token=417006b3cc7e1465d476fc20ae150d70

I have tried doing things, like setting the Gravity value to positive, and messing with the numbers and making them negatives/positives, higher/lower, etc. The closest i have gotten was setting the gravity to positive and making the destination 15 units higher, but the part just concaves downwards and does not appear again.

Anything will help!

Thanks!