How can i find inside area of the geometry (2d) ??

Hello everyone... can anyone please help me and educated me. I want to find the area covered inside this 2d geometry ?? Please let me know how to do it. I shall remain thankful. Please see the code attached.

clc 
clear all
close all

t1 = 0:pi/100:pi; % Top curve 0 to 180 deg
t2 = -pi:pi/100:0; % Bottom curve 180 to -180 deg
 
%%% Shape   
a1 = 375;  % width, x-axis
a2 = 375;   
b1 = 457;  % height, y-axis
b2 = 78;    

%%% Slope 
n1 = -1.43;  
m1 = 1.25;  
n2 = -1.0;  
m2 = 1.6;  

x1 = zeros(length(t1),length(n1));
y1 = x1;
z1 = x1*0

z1 = 101×1

0 0 0 0 0 0 0 0 0 0

leg1 = cell(length(n1),1);

x2 = zeros(length(t2),length(n2));
y2 = x2;
z2 = x2*0

z2 = 101×1

0 0 0 0 0 0 0 0 0 0

leg2 = cell(length(n2),1);
 
for i=1:length(n1)
    x1(:,i) = sign(cos(t1)).*a1.*abs(cos(t1)).^(2+n1(i));
    y1(:,i) = sign(sin(t1)).*b1.*abs(sin(t1)).^(2+m1(i));
    leg(i) = {['n1 = ',num2str(n1(i))]};
end

for i=1:length(n2)

    x2(:,i) = sign(cos(t2)).*a2.*abs(cos(t2)).^(2+n2(i));
    y2(:,i) = sign(sin(t2)).*b2.*abs(sin(t2)).^(2+m2(i));
    leg(i) = {['n2 = ',num2str(n2(i))]};
end
 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
figure(1)
xlabel('X-axis','fontweight','bold','fontsize',10)
ylabel('Y-axis','fontweight','bold','fontsize',10)
zlabel('Z-axis','fontweight','bold','fontsize',10)
plot3(z1,x1,y1,z2,x2,y2,'linewidth',2)

Answer 1

[Matt J]

 Area = polyarea([x1;x2],[y1;y2])

[Dr Sohaib Khan]

Thankyou soooooooooo much Matt. :) :) :)