algebra · worked example

Solve x² - 7x + 12 = 0

Method: factoring. Verified step-by-step solution with our free AI math solver.
Problem

x27x+12=0x^2 - 7x + 12 = 0

Step-by-step solution

  1. Find two numbers that multiply to 1212 and add to 7-7.

  2. Both must be negative (product positive, sum negative): 3-3 and 4-4 work since (3)(4)=12(-3)(-4) = 12 and 3+(4)=7-3 + (-4) = -7.

  3. Factor: (x3)(x4)=0(x - 3)(x - 4) = 0.

  4. Set each factor to zero: x=3x = 3 or x=4x = 4.

Answer

x=3orx=4x = 3 \quad \text{or} \quad x = 4

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