## bmorg980 3 years ago i need to complete the square of -36x^2-36x+27

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1. sasogeek

have you tried solving this?

2. bmorg980

yes. initially i divided each variable by 36, but then i got a bunch of fractions and it did not make sense to me. Do i need to divide by 36?

3. sasogeek

ok well that's a good start :) and yes you will end up with a bunch of fractions, it happens ;) i'll tell you what to do, try that, then let me know what answer you get... are we good?

4. bmorg980

5. bmorg980

ok, i got x^2+x+(1/2)^2=-27/36-1/4

6. sasogeek

uhhh close, but not quite. you should've divided by -36 that way you'd have $$\large x^2+x=\frac{27}{36}$$

7. sasogeek

sorry for late reply, i lost connection

8. bmorg980

ok, im going to try that. no problem, im doing some other problems while i wait

9. sasogeek

then with the next step, you'd get $$\large x^2+x+\frac{1}{4}=\frac{27}{36}+\frac{1}{4}$$

10. bmorg980

ok, i have x^2+x+1/4=1/2

11. sasogeek

$$\large \frac{27}{36}+\frac{1}{4}= what?$$

12. bmorg980

13. sasogeek

yeah :)

14. bmorg980

ok, now im a little confused, isnt it (x+b/2)^2. i dont know where to go from here

15. sasogeek

ok so you have $$\huge x^2+x+\frac{1}{4}=1$$ what you said is right, b=1, hence the next step is $$\huge (x+\frac{1}{2})^2=1$$ :)

16. bmorg980

no... i keep losing connection so bear with the reply timing :) what you do is solve for x.... the next step is to find the square root of both sides of the equation to clear the square on the left side... $$\huge x+\frac{1}{2}= \pm \sqrt{1}$$ $$\huge x= \pm \sqrt{1}-\frac{1}{2}$$ $$\huge x= \pm 1-\frac{1}{2}$$ solve for x now :)