## anonymous 4 years ago find the area of the triangle whose sides have the given lengths. a=9, b=12, c=15

1. anonymous

Do you know Heron's formula @Chiomatn93 ? Apply that and you will get your answer

2. anonymous
3. anonymous

$s= (9+12+15)/2 =18 now by heron's formula Area=\sqrt{18* (18-9) (18-12)(18-15)}$ \ [\sqrt{18*9*6*3} = \sqrt{2916} = 54 therefore your area is 54

4. anonymous

whats the answer and how do u solve?

5. anonymous

6. anonymous

@Chiomatn93 , Didn't you see the wiki link I gave above ?

7. anonymous

how do u solve it though? like the steps???

8. anonymous

Commo'n the formula is there, the quantities are given. Now can't you multiply and take the square root by yourself

9. anonymous

See the formula is $Area = \sqrt{s(s-a)(s-b)(s-c)}$ where $s= {a+b+c \over 2}$ where a , b, c are the length of the sides of the triangle. First find s. then substitute to get your Area ??

10. anonymous

damn calm down...jeez i will do but i just want an example

11. anonymous

see my reply solution is there

12. anonymous

13. anonymous

Ok first you would have to take out the s that is semi perimerter formula for s is S= (a +b +c)/2 here the S is 18 Area of triangle is $A=\sqrt{s*(s-a)*(s-b)*(s-c)}$ So the area would be now $A=\sqrt{18*(18-9)*(18-12)*(18-15)}$ $A=\sqrt{18*5*6*3}$ $A=\sqrt{2916}$ A=54 Therefore the area of triangle is A=54 which is your answer

14. anonymous

I cannot put it more simply

15. anonymous

thank you! i understand it much more now!