Now, the addition/subtraction method is used to eliminate one of the variables. We can do this to the above equation for x by multiplying the first equation by 2 and using the addition method. sf ( (A)) The expression for half - cell potential is: sf (E=E^@- (RT)/ (zF)ln [ [red]]/ ( [ ox ])) For a metal/metal ion system at 298 K this can be simplified to. One role of RNA is to be the mechanism for the expression DNA - transcribing and translating the genetic code into a protein that the cell requires to sustain itself. p (x)= (x-3) (x-3) (x-0) (x-0) (x+3) Expansion left as an exercise There's not enough data to identify M. It could be any of the group 1 metals (except maybe Lithium). Let's keep calling it M. Burning in air: 4M+O_2- 2M_2O so X=M_2O X reacting with water: M_2O+H_2O- 2MOH so Y=MOH M reacting with water: 2M+2H_2O- 2MOH+H_2 so Z=H_2 Y being heated: 2MOH- M_2O+H_2O See the proof below We need cotx =cosx/sinx Therefore, LHS=1-sinxcos=1-sinxcosxsinx/sinx =1-sin^2x(cosx/sinx) =1-sin^2xcotx =RHS QED If we can get down to one trig function, that would be best. y = 1/2(2sinxcosx) y =1/2sin(2x) This is the graph of a sinx with period pi and amplitude 1/2. Hopefully this helps! to find some choose any value for x and substitute into the equation PrecalculusGeometry of a ParabolaVertex Form of the Equation 1 Answer Vinícius Ferraz Feb 24, 2017 y = 5x^2 + 20x + 17 No, -1/6 Divide the numerator and denominator of the fraction by 3, so: - (3-:3)/ (18-:3)=-1/6 -1/6!=-6.