mjhjmtu

I want to make a table with two columns:

• on the left side, I want to put 2 aligned equations


• on the right side, I want to put a graph.

In the following MCVE, the 2 equations are on the left side but with a huge unused space between them. I want to place those 2 equation just next to the graph

documentclass[a4paper, 12pt]book
usepackagepgfplots, tikz
begindocument
begintabularcc
 $
 fracu_i+1,j - u_i,jDelta t = kappa fracu_i,j-1 - 2u_i,j + u_i,j+1(Delta x)^2$ \
 $u_i+1,j = u_i,j + frackappa Delta t(Delta x)^2(u_i,j-1 - 2u_i,j + u_i,j+1)
 $
 &
 begintikzpicture
 [scale = 0.7]
 %[scale = 0.7, every node/.style=scale = 0.7]
 % Draw axes
 draw [<->,thick] (0,5) node (yaxis) [above] $y$
 |- (5,0) node (xaxis) [right] $x$;

 coordinate (c) at (2,2);
 fill[red] (c) circle (3pt);
 draw[dashed] (yaxis |- c) node[left] $scriptstylei$
 -| (xaxis -| c) node[below] $scriptstylej-1$;

 coordinate (d) at (3,2);
 fill[red] (d) circle (3pt);
 draw[dashed] (yaxis |- d) node[left] $scriptstylei$
 -| (xaxis -| d) node[below] $scriptstylej$;

 coordinate (d) at (3,3);
 fill[red] (d) circle (3pt);
 draw[dashed] (yaxis |- d) node[left] $scriptstylei+1$
 -| (xaxis -| d) node[below] $scriptstylej$;

 coordinate (d) at (4,2);
 fill[red] (d) circle (3pt);
 draw[dashed] (yaxis |- d) node[left] $scriptstylei$
 -| (xaxis -| d) node[below] $scriptstylej+1$;

 draw [thin, gray] (0,0) grid (5,5);
 endtikzpicture\
endtabular
enddocument

I propose this somution with the equations inserted in a gathered environment,, and a raisebox for the graph:

documentclass[a4paper, 12pt]book
usepackagepgfplots, tikz
usepackagemathtools 

begindocument

begintabularcc
 leavevmode $ begingathered
 fracu_i+1,j - u_i,jDelta t = kappa fracu_i,j-1 - 2u_i,j + u_i,j+1(Delta x)^2 \
 u_i+1,j = u_i,j + frackappa Delta t(Delta x)^2(u_i,j-1 - 2u_i,j + u_i,j+1)
 endgathered $
 &
 raisebox-0.5height- d) node[left] $scriptstylei$
 -\
endtabular

enddocument