MATLAB: How to shade the area bounded by curves

area shading

I need to shade the area bounded by the curves y=x^2, the x-axis, and y= -(1/4)*x+(9/2) the color yellow. I can't figure out how to do this. I'm close, and I'm sure it's an easy fix, but here's what I have so far:
clc;clear;close all;
syms x;
par= int(x^2,0,2);
dy= diff(x^2);
lin= int(-(1/4)*x+(9/2),2,18);
y1=x^2;
y2=-(1/4)*x+(9/2);
area=(par+lin)
hold on
fplot('x^2',[0 2])
fplot('-(1/4)*x+(9/2)',[2 18])
%fill(x,y,'y')
hold off
title('Supplement 7: Problem 4')
axis equal; axis([0 20 0 5])
set(gca, 'Xtick', 0:20)
set(gca, 'Ytick', 0:5)
xlabel('x'); ylabel('y')

Best Answer

A somewhat simpler approach:
x=linspace(0, 18);
y=x.^2;
y2=x.*(-1./4)+(9./2);
y3=x.*0;
figure(1)
plot(x,y, x,y2, x,y3); grid on;
axis([-1,20,-1,5])
area(x, min([y; y2]), 'FaceColor','y')
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