Update WhatIs_Sprite.md (#151)

Corrected coordinates in the overview section

Author: jani-r

articles/getting_to_know/whatis/graphics/WhatIs_Sprite.md

@@ -17,7 +17,7 @@ Sprites are 2D bitmaps that are drawn directly to a render target without using
 
 ## Overview
 
-Sprites are positioned on the screen by coordinates. The width and height of the screen is the same as the back buffer. The x-axis represents the screen width and the y-axis represents the screen height. The y-axis is measured from the top of the screen and increases as you move **down** the screen, and the x-axis is measured from left to right. For example, when the graphics back buffer is 800×600, 0,0 is the upper left of the screen, and 800,600 is the lower right of the screen.
+Sprites are positioned on the screen by coordinates. The width and height of the screen is the same as the back buffer. The x-axis represents the screen width and the y-axis represents the screen height. The y-axis is measured from the top of the screen and increases as you move **down** the screen, and the x-axis is measured from left to right. For example, when the graphics back buffer is 800×600, the top left corner is at (0,0) and the bottom-right pixel is at (799,599).
 
 To draw a sprite, create a [SpriteBatch](xref:Microsoft.Xna.Framework.Graphics.SpriteBatch) object, initialize it by calling [Begin](/api/Microsoft.Xna.Framework.Graphics.SpriteBatch.html#Microsoft_Xna_Framework_Graphics_SpriteBatch_Begin_Microsoft_Xna_Framework_Graphics_SpriteSortMode_Microsoft_Xna_Framework_Graphics_BlendState_Microsoft_Xna_Framework_Graphics_SamplerState_Microsoft_Xna_Framework_Graphics_DepthStencilState_Microsoft_Xna_Framework_Graphics_RasterizerState_Microsoft_Xna_Framework_Graphics_Effect_System_Nullable_Microsoft_Xna_Framework_Matrix__), and then call [Draw](/api/Microsoft.Xna.Framework.Graphics.SpriteBatch.html#Microsoft_Xna_Framework_Graphics_SpriteBatch_Draw_Microsoft_Xna_Framework_Graphics_Texture2D_Microsoft_Xna_Framework_Rectangle_Microsoft_Xna_Framework_Color_) for each sprite. The bitmap data for a sprite is taken from a [Texture2D](xref:Microsoft.Xna.Framework.Graphics.Texture2D) object. The texture may contain alpha channel information to make part of the texture transparent or semi-transparent. You can tint, rotate, or scale sprites by using [Draw](/api/Microsoft.Xna.Framework.Graphics.SpriteBatch.html#Microsoft_Xna_Framework_Graphics_SpriteBatch_Draw_Microsoft_Xna_Framework_Graphics_Texture2D_Microsoft_Xna_Framework_Rectangle_Microsoft_Xna_Framework_Color_). This method also gives you the option of drawing only part of the texture on the screen. After you draw a sprite, call [End](/api/Microsoft.Xna.Framework.Graphics.SpriteBatch.html#Microsoft_Xna_Framework_Graphics_SpriteBatch_End) before calling [Present](xref:Microsoft.Xna.Framework.Graphics.GraphicsDevice.Present).