SOLUTION: Factor completeley 10a^2+ab-2b^2

Question 93561: Factor completeley
10a^2+ab-2b^2
Answer by checkley75(3666) (Show Source): You can put this solution on YOUR website!
YOU NEED TO FIND A SET OF FACTORS FROM THE NUMBERS 10 &-2 THAT WNEM MULTIPLIED TOGETHER AND THEN ADDED WILL=1.
FACTORS FOR 10=1&10,-1&-10,2&5,-2&-5.
FACTORS FOR -2=1&-2,-1&2.
THESE ARE ALL POSSIBLE FACTORS.
NOW SELECT ONE FACTOR FROM EACH GROUP & MULTIPLY IT BY ONE FACTOR FROM THE OTHER SET & ADD THE PRODUCTS. WHEN YOU GET A SUM OF 1 THEN YOU HAVE THE ANSWER.
1*1+10*-2=1-20=-19 IS NOT A GOOD CHOICE.
2*-1+5*2=-2+10=8 IS NOT A GOOD CHOICE.
5*1+2*-2=5-4=1 LOOKS LIKE A WINNER.
NOW USEING THE OUTER & INNER ITEMS OF THE FOIL PROCEDURE WE GET:
OUTER=5*1=5 INNER=-2*2-4 NOW ADD 5-4=1 THE MIDDLE TERM OF THE EQUATION.
-------------------------------------------------------------------------
10a^2+ab-2b^2
(5a-2b)(2a+b)
RELATED QUESTIONS
Factor completely... (answered by chitra)

factor completely.... (answered by checkley71)

factor by grouping,... (answered by JBarnum)

Factor theswe polynomials completely 54. 2x^2 -x - 10 80. 4m^2 + 20 + 25 60. 10a^2 + (answered by PackyMan)

Factor each polynomial. a^2-2a-35 Factor completely. -3t^3+ 3t^2-6t Factor... (answered by J2R2R)

10a^2-ab-21b^2 (answered by Alan3354)

Factor the polynomial completeley: Please help me. Appreciate it. 6x^2y^2 +12xy^2 +12y^2 (answered by oscargut)

factor out polynomial. 10a^3b^2-35a^2b+5a^4 thank... (answered by Mathtut)

Factor completely:... (answered by stanbon)