## anonymous 5 years ago solve by completing the square 12x^2+25x=7

1. anonymous

Hi this is the first time on this site, I am desperate on learning it

2. watchmath

$$12(x^2+\frac{25}{12}x)=7$$ $$12(x^2+\frac{25}{12}x)+12\cdot (25/24)^2=7+12\cdot(25/24)^2$$ $$12(x+(25/24) )^2=7+12\cdot(25/24)^2$$ $$(x+(25/24))^2=(7/12)+(25/24)^2$$ you can continue from there :)

3. anonymous

12x^2 25x 7 ------ + ---- = --- 12 12 12 25x 25 7 25 x^2 + ---- + ---- = --- + ---- (12)2 12 12 24 (x+25/24)^2=13/8 x+25/24 = sqrt(13/8) x=sqrt(13/8)-25/24 you can use calculator

4. anonymous

hope that helps and simplify further what has watchmath had started up in there

5. anonymous

dlugo did you understand the solution here?

6. anonymous

oooops here is a better one.... 12x^2 25x 7 ------ + ---- = --- 12 12 12 25x 25 7 25 x^2 + ---- + ---- = --- + ---- 12 2*12 12 24 (x+25/24)^2=13/8 x+25/24 = sqrt(13/8) x=sqrt(13/8)-25/24 you can use calculator