Recognize Polynomial Type: Recognize the type of polynomial and determine the factoring strategy. The given polynomial is a quadratic in the form of ax2+bx+c. We can attempt to factor it as a product of two binomials if it is factorable. The coefficients suggest that it might be a perfect square trinomial because 100 and 49 are perfect squares, and 140 is twice the product of the square roots of 100 and 49.
Write Perfect Squares: Write down the perfect squares of the coefficients of the quadratic polynomial.The square root of 100 is 10, and the square root of 49 is 7. The middle term coefficient, −140, is twice the product of 10 and 7, which is 2×10×7=140. This suggests that the polynomial might be a perfect square trinomial.
Check Perfect Square Trinomial: Write the polynomial in the form of (ax+b)2 to see if it matches the given polynomial.The perfect square trinomial would be (10−7x)2 because (10)2=100 and (7x)2=49x2 and the middle term would be 2×10×7x=140x, but we have −140x in the polynomial, so it should be (10−7x)2.
Expand to Verify: Expand (10−7x)2 to verify if it equals the given polynomial.(10 - 7x)^2 = (10 - 7x)(10 - 7x) = 100 - 70x - 70x + 49x^2 = 100 - 140x + 49x^2\.This matches the given polynomial exactly.
Write Final Factored Form: Write the final factored form of the polynomial. The factored form of the polynomial 100−140x+49x2 is (10−7x)2.
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