## Chiomatn93 Group Title find the area of the triangle whose sides have the given lengths. a=9, b=12, c=15 2 years ago 2 years ago

1. shivam_bhalla

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

2. shivam_bhalla
3. ipm1988

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

4. Chiomatn93

whats the answer and how do u solve?

5. ipm1988

6. shivam_bhalla

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

7. Chiomatn93

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

8. shivam_bhalla

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

9. shivam_bhalla

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. Chiomatn93

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

11. ipm1988

see my reply solution is there

12. Chiomatn93

13. ipm1988

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. ipm1988

I cannot put it more simply

15. Chiomatn93

thank you! i understand it much more now!