Subtracting polynomialsBefore, you start this lesson about subtracting polynomials, make sure you have mastered addition of polynomials Furthermore, you have to understand how to add and subtract integers There is no way around these or you will struggle! Example #1: Subtract 2x^{2} + 3x + 4 from 3x^{2} + 5x + 8 Step #1: Rewrite the problem 3x^{2} + 5x + 8 − (2x^{2} + 3x + 4) Replace minus sign by +  3x^{2} + 5x + 8 + (2x^{2} + 3x + 4) The negative sign will change the sign for every term inside the parenthesis. It is just like taking the opposite Therefore if something is positive, it will become negative. If it is negative, it will become positive 3x^{2} + 5x + 8 + (2x^{2} + 3x + 4) = 3x^{2} + 5x + 8 + 2x^{2} + 3x + 4 Combine all like terms. You could use parenthesis to keep things organized 3x^{2} + 5x + 8 + 2x^{2} + 3x + 4 = (3x^{2} + 2x^{2} ) + (5x + 3x) + 8 + 4 = (3 + 2) x^{2} + (5 + 3)x + 4 = 1x^{2} + (8)x + 4 = x^{2} + 8x + 4 Example #2: Subtract 4x^{2} + 6x + 5 from 8x^{2} + 4x + 8 Step #1: Rewrite the problem 8x^{2} + 4x + 8 − (4x^{2} + 6x + 5) Replace minus sign by +  8x^{2} + 4x + 8 + (4x^{2} + 6x + 5) The negative sign will change the sign for every term inside the parenthesis. It is just like taking the opposite Therefore, if something is positive, it will become negative. If it is negative, it will become positive 8x^{2} + 4x + 8 + (4x^{2} + 6x + 5) = 8x^{2} + 4x + 8 + 4x^{2} + 6x + 5 Combine all like terms. You could use parenthesis to keep things organized 8x^{2} + 4x + 8 + 4x^{2} + 6x + 5 = (8x^{2} + 4x^{2} ) + (4x + 6x) + 8 + 5 = (8 + 4) x^{2} + (4 + 6)x + 3 = (12)x^{2} + (10)x + 3 = 12x^{2} + 10x + 3 I did not use algebra tiles for this lesson about subtracting polynomials. Any problems, use the form here to send your questions 




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