# Ho to enter this equation and plot it

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mohamed mohamed on 5 Nov 2015
Commented: Walter Roberson on 5 Nov 2015
X=10:50;
w=.2:1.2;
y=(230-(x*.2))/(.5+w);
every time it show
error using / .
Matrix dimensions must agree
finally i need to plot the answer in 2d x&y

TastyPastry on 5 Nov 2015
Well you can't do either right matrix or element by element division on the vectors X and w. X is 1x41 while w is 1x2. I'm assuming you need to do element by element division, which is ./, but even then, that wouldn't work since your vectors aren't the same size.
mohamed mohamed on 5 Nov 2015
I want to divide(230-(x*.2))/(.5+w) so that w will take different number from (.2:1.2) the value of w will reach 1.2 at x=30 then w remains constant and only x will change so that i can perform element by element division

Thorsten on 5 Nov 2015
Edited: Thorsten on 5 Nov 2015
I'm not sure what you want, but if you want to evaluate y for every combination of x and w on a 2D grid, you can use:
x=10:50; w=0:0.2:1.2;
[X, W] = meshgrid(x,w);
y=(230-(X*.2))./(.5+W);
surfl(y)
Note that I used a differed w with more than just 2 values such that you can use surfl.
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Walter Roberson on 5 Nov 2015
If it gave you the warning about rank deficient then you used / instead of ./