Absorbance vs Concentration discussion

For the standard solutions (S1-S6), we can assume that the initial SCN- concentration is equal to the final equilibrium concentration of FeNCS2+. Plot the S1-S6 concentration of FeNCS2+ on the x axis against their absorbances on the y axis, and use the equation from your trendline to find the concentration of FeNCS2+ in solutions E1-E6. To do this, substitute your E1-E6 absorbance values into the trendline’s equation as y-values, and solve for x to get the equilibrium concentration of FeNCS2+ in E1-E6.

Please show all steps. Thank you so much I appreciate this a lot.