Question

How do you find the area of `triangle RST` given t=15.7, s=15.7, `mangleR=98`?

Answer 1

`122.05`

Explanation:

Given that `RS=RT=15.7, DeltaRST` is isosceles.
`=> angle RST = angleRTS=(180-98)/2=41`
`=> h=15.7xxsin41^@=10.30`
`=> ST=15.7xxcos41xx2=23.70`
`=> Area = 1/2xxhxxb`, where h is the height and b is the base.
`=> Area = 1/2xx10.30xx23.70=122.05`

Alternatively, you can use the following formula to find the area :

`Area = 1/2xxSR^2xxsin(m angleR)`
`= 1/2xx15.7^2xxsin98^@=122.05`