How can solve this first order ODE using ODE45? I used the function but I don't get what I want

dt/dx = 1+4.5(1-X)/ 3.5(1-X)

tspan= [0 10];
x0 = 0;
fun = (1+4.5*(1-x)/3.5*(1-x)); 
[t,x] = ode45(@(t,x)(1+4.5*(1-x)/3.5*(1-x)),tspan,x0);
plot(t,x,'o-')
xlabel('Time (hr)')
ylabel('Conversion')
title(' Time Vs Conversion) 
legend('Conversion')
ylim([0 1.1])