<P> In microeconomic theory, the Marginal Rate of Technical Substitution (MRTS)--or Technical Rate of Substitution (TRS)--is the amount by which the quantity of one input has to be reduced (− Δ x 2 (\ displaystyle - \ Delta x_ (2))) when one extra unit of another input is used (Δ x 1 = 1 (\ displaystyle \ Delta x_ (1) = 1)), so that output remains constant (y = y _̄ (\ displaystyle y = (\ bar (y)))). </P> <P> M R T S (x 1, x 2) = − Δ x 2 Δ x 1 = M P 1 M P 2 (\ displaystyle MRTS (x_ (1), x_ (2)) = - (\ frac (\ Delta x_ (2)) (\ Delta x_ (1))) = (\ frac (MP_ (1)) (MP_ (2)))) </P>

What does marginal rate of technical substitution mean
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