Factoring Trinomials Math Example 4

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Example 4

medium
Factor x2+2x−15x^2 + 2x - 15.

Solution

  1. 1
    Find two numbers: 5×(−3)=−155 \times (-3) = -15 and 5+(−3)=25 + (-3) = 2.
  2. 2
    (x+5)(x−3)(x + 5)(x - 3).

Answer

(x+5)(x−3)(x + 5)(x - 3)
When c<0c < 0, the two numbers have opposite signs. The larger absolute value takes the sign of bb (positive here), giving +5+5 and −3-3.

About Factoring Trinomials

Factoring a trinomial of the form ax2+bx+cax^2 + bx + c into a product of two binomials by finding two numbers that multiply to acac and add to bb.

Learn more about Factoring Trinomials →

More Factoring Trinomials Examples

Example 1 easy

Factor [formula].

Example 2 hard

Factor [formula] using the AC method.

Example 3 easy

Factor [formula].

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