Question: An ichthyologist tracks two fish species' population trends with lines $ y = -3x + 18 $ (species A) and $ y = 4x - 2 $ (species B). Find their intersection point.

["Title: How Ichthyologists Track Fish Populations: Finding the Intersection of Two Species’ Trends", "---", "Understanding Fish Population Dynamics\nIchthyologists, scientists who study fish, often analyze the population trends of different species across time and environment. By using mathematical models, they can predict when and where species coexist or compete. In one compelling study, researchers tracked two fish populations using linear equations: species A modeled by $ y = -3x + 18 $ and species B by $ y = 4x - 2 $. Determining their intersection point reveals critical insights—when and where these populations overlap, signaling potential ecological interactions.", "---", "Tracing the Population Trends\nThe equation for species A:\n$$ y = -3x + 18 $$\nThis negative slope indicates the population decreases by 3 individuals per unit time ($ x $), starting from 18 fish when $ x = 0 $.", "Species B is modeled by:\n$$ y = 4x - 2 $$\nWith a positive slope of 4, this population grows by 4 individuals per unit time, starting at just 2 fish.", "These contrasting trends set the stage for a meaningful intersection: where the declining population of species A meets the rising trajectory of species B.", "---", "Finding the Intersection Point\nTo locate the exact time $ x $ and population size $ y $ where both species have the same population, solve the system:\n$$\n\begin{align}\ny &= -3x + 18 \\ny &= 4x - 2\n\end{align}\n$$", "Set the right-hand sides equal:\n$$ -3x + 18 = 4x - 2 $$", "Now solve for $ x $:\n$$\n\begin{align}\n-3x - 4x &= -2 - 18 \\n-7x &= -20 \\nx &= \frac{20}{7}\n\end{align}\n$$", "Substitute $ x = \frac{20}{7} $ into one of the equations to find $ y $. Using species A’s model:\n$$\ny = -3\left(\frac{20}{7}\right) + 18 = -\frac{60}{7} + \frac{126}{7} = \frac{66}{7}\n$$", "---", "Conclusion: A Key Ecological Milestone\nThe populations of species A and B intersect at the point $ \left(\frac{20}{7}, \frac{66}{7}\right) $. This moment, roughly 2.86 time units into the study, marks the first time both species share the same population size. For ichthyologists, such intersections help forecast competition, migration patterns, or habitat shifts—critical for conservation and ecosystem management.", "Using linear models, researchers can accurately pinpoint these pivotal ecological snapshots, turning abstract equations into vital data for protecting aquatic biodiversity.", "---", "Keywords: ichthyologist, fish population, species A, species B, population trend analysis, mathematical modeling, intersection point, negative slope population, positive slope population, ecological interactions, math in biology, linear equations ecology", "---", "Unlock the science behind fish conservation—understand how lines intersect to reveal deeper truths about our aquatic world."]