Microsoft Office Tutorials and References

In Depth Information

3x –8 = –4y

3x + 4y = 8

2.
Place the coefficients in an
n
x
n
range of cells, where
n
represents the number of equations. In Figure 10-5,

the coefficients are in the range I2:J3.

3.
Place the constants (the numbers on the right side of the equal sign) in a vertical range of cells. In Figure

10-5, the constants are in the range L2:L3.

4.
Use an array formula to calculate the inverse of the coefficient matrix. In Figure 10-5, the following array

formula is entered into the range I6:J7. (Remember to press Ctrl+Shift+Enter to enter an array formula, and

omit the curly brackets.)

{=MINVERSE(I2:J3)}

5.
Use an array formula to multiply the inverse of the coefficient matrix by the constant matrix. In Figure

10-5, the following array formula is entered into the range J10:J11. This range holds the solution.

{=MMULT(I6:J7,L2:L3)}

See Chapter 14 for more information on array formulas.

Figure 10-5:
Using formulas to solve simultaneous equations.

You can access the workbook, simultaneous equations.xlsx, shown in Figure 10-5, from

this book's website. This workbook solves simultaneous equations with two or three

variables.