SAT Question 3a9d60b2: Nonlinear Equations In One Variable And Systems Of Equations In Two Variables answer and explanation with Desmos solution

Combining like terms gives $5\left|4-x\right|=25$, so $\left|4-x\right|=5$. This means $x$ is 5 units from 4, so $x=4-5=-1$ or $x=4+5=9$. Therefore, the positive solution is $9$.