How to derive EV/EBITDA, EV/Sale and EV/EBIT formulas

Dear all,

I read a training document which show the formulas for EV/EBITDA, EV/Sale and EV/EBIT (single stage). But I don’t understand and don’t know how these formulas are derived. Please kindly help me understand these formulas below:

g is long term growth rate

T is tax rate

D is depreciation

M is operating margin

Thanks you so much

g = ROE * (1 - dividend payout)

ROE = Net income/shareholder equity

WACC = ((Debt/(Debt+Equity+Pref. Shares))*(1-T)*(cost of debt))+((Equity/(Debt + Equity + Pref. Shares))*cost of equity (CAPM))+((Pref. Equity/(Debt + Equity + Pref. Equity)*(cost of Pref Equity))

CAPM = rf + beta(market risk - rf)

ROIC = (Net income - Dividends)/(Debt + Equity)