go to this link and solve the triangle and circle picture question https://www.google.co.th/search?tbs=sbi:AMhZZisoTtKGvxP8DNQDJB6z2RfKcsD2aKcFxjeVFSZsjMR15f1nf8mCVMLqvHrB6gJSKagDP_1f82qLzarRSkcTukB3pt7aS8OT8irzB3Gk5q1VyxaPCAvUc0BF50wo_1eColRi1gUUR0Ec7Bd_1Pvof_1A1TRmCBes7gWLDDd_19Z4ic_1Av4kHiJwIsLzeRLTi4PyfVpq9k50Npf7HL44SheQS1fqQMAlI3wdm3tbdGsU-2Ol5iVjUvvz15Wji_1AV0XT38HvGZD4FqENRMWUiVAnfqJ4ZYWQa7mqdPuoeC3r2FVRJUBAKYgj-DWuxqAR6U2JzvwI0F2EO_1FSHXCzDs3yR_1rADS3DbQOAYP2CAFpCeKUYsG6eA4eMdJ_16II4JDGX6LRcWAeIwQe3U5gcpkTMQf28qZLoMdge7m1cDGu5absgGQB_1dtDYsnMW_12_1NPqOkww1-hTvEw5RUHSgt9Stjb5y2-l-gKGk9wIOavFiixwoGev-QGlYl0b-N76VNPW4SwmQfekoLdzmIllHYQlfAW9dI4DFSNQYMcextlzvxCSs4-ySZZ1QVmFRd8ucHTbM4mKBH9p9BRPWKhf_1aBlYOnIv0vJWzeru9Uijm4DbMySaphwmGD_1h2bMn6-FMuFEYLsWeadVKNHG0VB0BlW4LXK4ExA3oFfdZaeg&btnG=Search%20by%20image&hl=en-TH#
+118667 I think this is the image that you mean but I cannot read the writing.
+129849 Unfortunately....I can't tell what the shaded region is in the picture
But 1/2 the area of the equilateral triangle ≈ 21.65 cm
Assuming that the apex of the triangle lies at the circle's center....if the shaded region is the one bounded by the top part of the triangle and the bottom of the circle.....the radius can be found thusly:
Area of the shaded region = 1/2 the area of the equilateral triangle = 1/6 the area of the circle....so....
21.65 = (pi * r^2/ 6 multiply both sides by 6
129.9 = pi * r^2 divide both sides by pi
129.9/ pi = r^2 take the square root of both sides
r ≈ 6.43 cm
However.....if the bounded region is just the top part of the circle lying outside the triangle.....1/2 the area of the equilateral triangle = the area of 5/6 of the circle....and we have
21.65 = (5/6) pi r^2 divide both sides by 5pi/6
[21.65] / [ 5pi/6 ] = r^2 take the square root of both sides
r ≈ 2.88 cm
I suspect, from the results and given the picture....that the frist assumption is correct....that the shaded area is between the top of the triangle and the bottom of the circle
