clc
clear

disp("kaliyah johnson")

x = -3:0.1:3;

y = 3*x.^4 - 6*x.^3 + 8*x.^2 + 4*x + 90;
z = 3*x.^3 + 5*x.^2 - 8*x + 70;

plot(x,y,x,z)

xlabel('Voltage')
ylabel('Current')
legend('y','z')