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Alexandra-morales24
Given the following perfect square trinomial, fill in the missing term. (Do not type the variable in the blank.) 4x2 + ___x + 49
the two square roots involved are 2 and 7 so arithmetic on these will give you the missing number
well, our options for this would suggest that: (2x)^2 + nx + (7)^2 comes form either: (2x+7)^2 or (2x-7)^2 ; the + on the middle term would indicate the first
since 49 is apart of the square a term must be its square root i.e. 7 and sincce the other square term is 4x^2...then the term before squaring must be its square root i.e. 2x... so (2x + 7)^2 = 4x^2 + 28x + 49
The answer would be 4x^2+ 14x+49 You take the square root of 49 and then take that answer (which is 7) and multiply it by 2. Hope this helps!
Zhang, that only works if the first term is an x^2; we got a 4 in the way this time to do that we would have to divide off the 4 and work it out
but, i spose the wrong answer is the best answer :) lol
(2x+7)^2 = 4x^2 +28x + 49
@amistre64 is my answer is wrong??
you should be able to dbl chk it to determine that, but as is, your answer is wrong. You did not account for the 4 on the first term
oh right lol sorry it was 28
(ax+b)^2 = (ax)^2 + 2ab x + b^2 sqrt(b^2) * 2 = 2b but that only works if a=1, otherwise we have to adjust it for a