Excel for Marketing Managers

Solving Systems of Equations

Solving
Systems of
Equations

h. Now that you know the value of x, you can substitute it back into one of

the original equations and solve for y. You will use Equation 1 to do

this. In cell Q21, enter the following formula:

=(q9-k9*q20)/n9

The number displayed in this cell should be 120.

i. The equations in rows 23 and 25 will put the answers from cells Q20

and Q21 back into the original equations. If the answers are correct, the

numbers to the right of the equal sign in rows 23 and 25 will be the

same as the number to the right in the original equation. In cell K23,

enter the following formula:

=k9

You can then copy (Ctrl+C) and paste (Ctrl+V) that formula into N23.

9. In order to maintain the correct cell color, you will need to use Paste
   Special to copy the formula into cells K25 and N25. To do this, click again
   on cell K23. Then, from the Edit menu, select Paste Special → Formulas
   and press Enter. Only the formula will get copied. Then click on cell N25
   and do the same. Since the original equations were set up with the same
   relative spacing of the equations in rows 23 and 25, you can copy the formu-
   las this way without error.

Figure 265

Using Paste special to copy formulas