How do you simplify 12r+5s-7t+11r+9s-4r

When a formula is solved for a particular variable, several different equivalent forms may be possible. if we solved a=1/2bh for h, one possible correct answer is h=2a/b . which one of the following is not equivalent to this? a. h= 2(a/b) b. h= 2a(1/b) c. h= a/1/2b d. h= 1/2a/b

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Find dy/dx using implicit differentiation ln(20+e^xy)=y