a.galvan2 2 years ago 9x^2+30x+25=64

1. ParthKohli

A good start is subtracting 64 from both sides.$\color{Black}{\Rightarrow 9x^2 + 3x + 25 - 64 = 0}$ Simplify, and solve the quadratic equation.

2. a.galvan2

the 9x^2 is what I am confused about.

3. Ganpat

confused ??

4. Ganpat

u can solve it by factorization...

5. BougyMan

(9x^2+3x)(25-64)

6. Ganpat

9x2+30x+25=64 9x2+30x+25-64 = 0 9x2+30x-39 = 0 9x2 -9x + 39x -39 = 0 9x(x-1) +39 (x-1) = 0 (9x +39) (x-1) = 0 so, x = -39/9 and x =1....

7. a.galvan2

sorry, but I do know the answer involves imaginary numbers.

8. agentx5

Actually no... The solutions for x as an answer does not involve imaginary #'s, and it's not 59/3

9. agentx5

@Ganpat is correct.

10. cornitodisc

11. agentx5

With the imaginary line, it's the intersection: |dw:1343664593480:dw|

12. a.galvan2

The answer in the back of the book is $x=(-10+2i \sqrt14)/6, (-10-2i \sqrt14)/6$ I just can't figure out how it got there.

13. agentx5

The blue line is (3x+5)^2 The imaginary line is 64i

14. agentx5

That answer is crazy, this has solvable real number values. Yes you can combine those to get X, but why?

15. agentx5

In this case I'd say either the problem was written down for us incorrectly/incomplete-directions, or the book is making it a whole lot harder than it needs be...

16. a.galvan2

i do not know.

17. agentx5

:-S Go with what @Ganpat said, unless there's something missing or incorrect here with regards to the question and it's directions as you wrote it here. He's 100% correct.

18. agentx5

Plug in those values for x and you'll it works.

19. Ganpat

@agentx5 : when did i say that ? :D.. lol

20. agentx5

Huh? o_O

21. Ganpat

kidding dude !! :)

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