Solve the equation by completing the square: x^2 + 2x = 120

Question

anonymous · Answer

@jazzyfa30 DO U KNW HW TO SOLVE A QUADRATIC EQUATION USING THE METHOD OF COMPLETING SQUARE???

jazzyfa30 · Answer

no

anonymous · Answer

DO U KNW THE ALZEBRAIC IDENTITY (A+B)^2=A^2+2AB+B^2

jazzyfa30 · Answer

no

anonymous · Answer

so let us first discuss the alzebraic identity (a+B)^2=a^2+2ab+b^2

anonymous · Answer

let us the find the square of 125=125^2=???
nw let us apply the identity here 
we can split 125 as 100+25
125^2=(100+25)^2

anonymous · Answer

nw in the above example a=100 b=25
nw a^2+2ab+b^2=100^+2.100.25+25^2
=10000+5000+625=15625 threfore 125^2=15625

jazzyfa30 · Answer

what do u have a skype

anonymous · Answer

multiplying 125 and 125 will take a lot of time but applying the identity in the example will of course save some time

anonymous · Answer

have u understood the identity @jazzyfa30??? if yes then let's come to ur question

jazzyfa30 · Answer

no thats y i asked u whether u had a skype so u could explain it verbally cus im not a visible learner

anonymous · Answer

x=-12,10

anonymous · Answer

jazzyfa30 · Answer

@pascuzzoa please dont give me the answer

anonymous · Answer

oops, well its to late now

anonymous · Answer

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