Hello, atreyyu!

Did you sketch the graphs?

Determine the number of solutions of the following system, depending on the value of .

. .

The graph of [1] looks like this:Code:| 1* * | * * | * * | * - - * - - - + - - - * - - -1 * | * 1 * | * * | * -1* |

The graph of [2] looks like this:Code:| * | * * | * * | * * | * a* | - - - - - - + - - - - - - |

Superimpose the two graphs and "slide" up and down the y-axis

. . and you will observe the following . . .

. .