How to make a graph in latex?

Someone help me to make the following graph in latex. I am a beginner or practically new to latex graphics.

• There's an rror on this draawing: the abscissa of the intersection is not 400/45, but 4000/45=800/9. May 31, 2021 at 20:51
• Yes, I had that error. In the accounts I made I have 4000/45 and I just put something else. May 31, 2021 at 21:00
• Have you looked at the pgfplots package? May 31, 2021 at 21:28

If you compile this:

\documentclass{article}
\usepackage{tikz}
\begin{document}
\begin{center}
\begin{tikzpicture}[scale=.1]
\coordinate (i) at (800/9,2600/27);
\coordinate (j) at (800/9,0);
\draw (-5,0)--(100,0);
\draw (0,-5)--(0,125);
\draw[thick,domain=0:100] plot (\x,{(7*\x/4-3*(\x/10)*(\x/10)/4});
\draw[thick,domain=0:100] plot (\x,{(3*\x/4+3*(\x/10)*(\x/10)/8});
\draw[dashed] (j)--(i);
\node[above left] at (60,78) {$7000x-30x^2$};
\node[above left] at (100,112) {$3000x+15x^2$};
\node at (50,60) {$A$};
\node at (i) {$\bullet$};
\node at (0,0) {$\bullet$};
\node[below left] at (0,0) {$0$};
\node[below] at (j) {$\frac{800}9$};
\end{tikzpicture}
\end{center}
\end{document}


you will get this:

• Thank you. Could you explain to me how you did it or in what program, or what pdf's I use to do it. I really would like to learn how to make these types of graphs. May 31, 2021 at 21:55
• I did it using TikZ. May 31, 2021 at 21:56