總需求和總供給曲線求方程式 - 經濟

Consider an economy characterized by the following relationships :
Consumption C=20+0.8(Y-T)
Investment I=620-4000r
Government Expenditure G=400
Taxes T=0.25Y-100
Money Demand Md=P(25+0.2Y-1000r)
Money Supply Ms=345
Nominal Wage W=10
Production Function Y=200N^1/2

(1) Derive the IS and LM equations and demonstrate that each has the “proper
” slope.
(2) Derive the aggregate demand equation and demonstrate that it has the ‘
proper” slope.
(3) Derive the aggregate supply equation and demonstrate that it has the ‘
proper” slope.


我主要是問2和3 is和lm的曲線就由g+i=s+t和money demand=money supply求就可以了
那as和ad呢 我記得這兩條線都是由畫圖找出來的
可是方程式要怎麼寫呢

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