[经] combined demand and supply curve
xū yào yǔ gōng jǐ zōng hé qū xiàn ㄒㄩ ㄧㄠˋ ㄩˇ ㄍㄨㄥ ㄐㄧˇ ㄗㄨㄥ ㄏㄜˊ ㄑㄩ ㄒㄧㄢˋ