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ROBERT3
Find the lowest common denominator for the set of fractions. 7/x^2+4x+4 5/4-x^2
the reqd LCM is 35/(x+2)
lcm of fraction is lcm of numerator /hcf of denominator thus lcm of 7 and 5 here is 35 and hcf of (x+2)^2 and (2+x)(2-x) is (x+2) hence the result
The denominator for the first one factors out to (x+2)(x+2). You get this by taking the coefficient of "4" and finding mult's that if adding together would give you the middle x term which is +4, then you would have x^2+2x+2x+4, you would use factor by grouping,(x^2+2x)(2x+4). Pull out the x from the first group, than a 2 from the second group. This will leave you with (x+2)(x+2). Now, the second part is "perfect squares," it is simply (2-x)(2+x). Now, with both of those done you come up with the final answer: (x+2)(2-x)is you LCD. If you are asking why not the (2+x), it is because that one is exact same as the (x+2), just written different but still the same value.
@ROBERT3 u r right we should multiply both side by (x+2)(2-x) after that we have a equation to solve
in my answer is 2x+(x+2) is correct @amir.sat
i need help @ajprincess
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getting it @robert3?