Chapter 10 - Radical Expressions and Equations - 10-5 Graphing Square Root Functions - Practice and Problem-Solving Exercises - Page 629: 12

$ x \geq \frac{13}{4} $

You can not take the square root of a negative number. Therefore, $4x - 13$ must be greater than or equal to 0. $ 4x - 13 \geq 0$ We add 13 to both sides $ 4x - 13 + 13 \geq 0 + 13$ $ 4x \geq 13$ We divide four from both sides $ x \geq \frac{13}{4} $