1. 1x3 - 26x2 + 48x Take out x x(1x2 - 26x + 48) Multiply the +48 times the 1 before the x2, getting +48 I. Think of two numbers which A) multiply to give +48 and which also B) combine to give -26 It doesn't take long to think of -2 and -24 because A) -2 TIMES -24 gives +48 and B) -2 PLUS -24 gives -26 II. Write -26x using -2 and -24 -26x = -2x - 24x III. Replace -26x in x(x2 - 26x + 48) with -2x - 24x x(x2 - 2x - 24x + 48) IV. Change the parentheses to brackets: x[x2 - 2x - 24x + 48] V. Factor out x in the first two terms in the brackets x[x(x - 2) - 24x + 48] VI. Factor out -24 in the last two terms in the brackets x[x(x - 2) - 24(x - 2)] VII. Factor out the common factor (x - 2) within the brackets x[(x - 2)(x - 24)] VIII. Erase the brackets: x(x - 2)(x - 24) ------------------------------------ 2. x2 - 6wy + 3xy - 2wx I. We can't factor the first two terms, so we must rearrange terms x2 + 3xy - 2wx - 6wy II. Factor x out of the first two terms x(x + 3y) - 2wx - 6wy III. Factor -2w out of the last two terms x(x + 3y) - 2w(x + 3y) IV. Factor out common factor (x + 3y) (x + 3y)(x - 2w) ----------------------------- 3. 1x2 - 5x - 14 Multiply the -14 times the 1 before the x2, getting -14 I. Think of two numbers which A) multiply to give -14 and which also B) combine to give -5 It doesn't take long to think of -7 and +2 because A) -7 TIMES +2 gives -14 and B) -7 PLUS +2 gives -5 II. Write -5x using -7 and +2 -5x = -7x + 2x III. Replace -5x in x2 - 5x - 14 with -7x + 2x x2 - 7x + 2x - 14 IV. Factor x out of the first two terms: x(x - 7) + 2x - 14 V. Factor +2 out of the last two terms: x(x - 7) + 2(x - 7) VI. Factor out common factor (x - 7) (x - 7)(x + 2) ------------------------ 4. 4x2 - 36y2 First factor out 4 4(x2 - 9y2) Change parentheses to brackets and write each as a perfect square 4[(x)2 - (3y)2] This is the difference of two perfect squares Learn formula: A2 - B2 factors as (A - B)(A + B) 4[(x) - (3y)][(x) + (3y)] Remover the inner parentheses 4[x - 3y][x + 3y] Change brackets to parentheses 4(x - 3y)(x + 3y) ------------------------------- 5. 3x2 - 2x - 8 Multiply the -8 times the 3 before the x2, getting -24 I. Think of two numbers which A) multiply to give -24 and which also B) combine to give -2 It doesn't take long to think of -6 and +4 because A) -6 TIMES +4 gives -24 and B) -6 PLUS +4 gives -2 II. Write -2x using -6 and +4 -2x = -6x + 4x III. Replace -2x in 3x2 - 2x - 8 with -6x + 4x 3x2 - 6x + 4x - 8 IV. Factor 3x out of the first two terms: 3x(x - 2) + 4x - 8 V. Factor +4 out of the last two terms: 3x(x - 2) + 4(x - 2) VI. Factor out common factor (x - 2) (x - 2)(3x + 4) ---------------------------- 6. 24x2 + 10x - 4 Take out 2 2(12x2 + 5x - 2) Multiply the -2 times the 12 before the x2, getting -24 I. Think of two numbers which A) multiply to give -24 and which also B) combine to give +5 It doesn't take long to think of +8 and -3 because A) +8 TIMES -3 gives -24 and B) +8 PLUS -3 gives +5 II. Write +5x using +8 and -3 +5x = +8x - 3x III. Replace +5x in 2(12x2 + 5x - 2) with +8x - 3x 2(12x2 + 8x - 3x - 2) IV. Change the parentheses to brackets: 2(12x2 + 8x - 3x - 2) V. Factor out 4x in the first two terms in the brackets 2[4x(3x + 2) - 3x - 2] VI. Factor out -1 in the last two terms in the brackets 2[4x(3x + 2) - 1(3x + 2)] VII. Factor out the common factor (3x + 2) within the brackets 2[(3x + 2)(4x - 1)] VIII. Erase the brackets: 2(3x + 2)(4x - 1) Edwin AnlytcPhil@aol.com