Grade seven, Edexcel GCSE Maths

Revision Notes

How do we use graphs to solve equations?
  1. Solutions are always read off the x-axis.
  2. Solutions of f(x) = 0 are where the graph of y = f(x) cuts the x-axis.
  3. If given g(x)=0 instead (Q: “by drawing a suitable straight line”) then:
    • Rearrange into f(x) = mx + c and draw the line y = mx + c
    • Solutions are the x-coordinates of where the line crosses the curve

Solutions may also be called roots.

Example

Solving equations using graphs Example 1, IGCSE & GCSE Maths revision notes

Cubic-Linear-Intersections-(before), IGCSE & GCSE Maths revision notes

using graphs Example 2, IGCSE & GCSE Maths revision notes

Cubic-Linear-Intersections-(after), IGCSE & GCSE Maths revision notes

Solving equations using graphs Example 3, IGCSE & GCSE Maths revision notes

Question

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Edexcel GCSE Maths Notes

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