知识点 2

Interpret the solution as the intersection point of two lines.

The solution to a system is the point where the two lines intersect.

核心知识

The solution to a system of two linear equations is the point where the two lines intersect on the coordinate plane.

深入理解

The solution is the intersection point. Every point on a line satisfies that line's equation; the solution to a system is the point that satisfies both.

  • Solve algebraically and get a coordinate pair, or read the intersection from the graph.
  • That pair must work in both equations.
  • If a point works in only one equation, it is not the solution.

常见误解

  • Confusing the 𝑥-intercept or 𝑦-intercept of a single line with the intersection of two lines.
  • Reading the intersection from a graph but swapping 𝑥 and 𝑦 — reporting (1,3) instead of (3,1).
题目

示例解析

Line 𝑝 is defined by 𝑦 =2𝑥 1 and line 𝑞 is defined by 𝑦 = 𝑥 +5. At what point do lines 𝑝 and 𝑞 intersect?

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