In Example 4, change the left side of the first equation from 5x² + 2y² to 2x² + 5y² and then solve the system.

Data from Example 4

By addition or subtraction, solve the system of equations

Multiplying the second equation by 2, and subtracting the resulting equations, we have

The corresponding values of y for each value of x are ±1. Again, we have four solutions:

Each solution checks when substituted in the original equations. The graphical solutions are shown in Fig. 14.12.

5x + 2y2 = 17 x2 x + y = 4