Please help me find the answer

Question

Given sin(x) = 1/8 with 0 deg < x < 90 deg and sin(y) = 7/9 with 0 deg < y < 90 deg Find sin(x + y)

Answer 1

x = (sqr32 +7sqr63)/72 = about .85

if sinx =1/8

siny = 7/9,

x and y each in quadrant 1

use trig identity

sin(x+y) = sinxcosy +sinycosx

and calculate cosx and cosy using the Pythagorean Theorem

cosx = sqr(8^2-1^2)/8

cosy = sqr(9^2-7^2)/9

plug in the values

sin(x+y)= sinxcosy+sinycosx = (7/9)(sqr32)/8 +(7/9)(sqr63)/9 = about.85