SOLUTION: How do you find the term that should be added to the expression to make a perfect square trinomial? x^2 + 11x x^2 + 4/5x how?

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Question 141902: How do you find the term that should be added to the expression to make a perfect square trinomial?
x^2 + 11x
x^2 + 4/5x
how?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
To make the trinomials perfect square trinomials, you must add the square of half the x-coeffecient, as long as the x^2-coefficient is 1.
x%5E2%2B11x The x%5E2-coefficient is 1 so add the square of half the x-coefficient. Add %2811%2F2%29%5E2+=+121%2F4 to get:
x%5E2%2B11x%2B121%2F4
Check:
x%5E2%2B11x%2B121%2F4+=+%28x%2B11%2F2%29%28x%2B11%2F2%29=%28x%2B11%2F2%29%5E2
Likewise for:
x%5E2%2B%284%2F5%29x Add %28%281%2F2%29%284%2F5%29%29%5E2+=+%284%2F10%29%5E2 = 16%2F100+=+4%2F25 to get:
x%5E2%2B%284%2F5%29x%2B4%2F25