1. **Problem statement:** Calculate the missing angle in each diagram where all angles at a point add up to 360°. 2. **Formula:** Sum of angles at a point = 360°. 3. **Explanation:** To find the missing angle, add all known angles and subtract from 360°. 4. **Calculations:** **a)** $x + 144 + 42 + 110 = 360$ $$x + 296 = 360$$ $$x = 360 - 296$$ $$x = 64°$$ **b)** $y + 39 + 30 + 122 = 360$ $$y + 191 = 360$$ $$y = 360 - 191$$ $$y = 169°$$ **c)** $a + 165 + 29 + 47 = 360$ $$a + 241 = 360$$ $$a = 360 - 241$$ $$a = 119°$$ **d)** $n + 83 + 47 + 65 = 360$ $$n + 195 = 360$$ $$n = 360 - 195$$ $$n = 165°$$ **f)** $k + 168 + 36 = 360$ $$k + 204 = 360$$ $$k = 360 - 204$$ $$k = 156°$$ **g)** $e + 71 + 109 = 360$ $$e + 180 = 360$$ $$e = 360 - 180$$ $$e = 180°$$ **h)** $h + 126 + 99 = 360$ $$h + 225 = 360$$ $$h = 360 - 225$$ $$h = 135°$$ **i)** $w + 83 = 360$ $$w = 360 - 83$$ $$w = 277°$$ 5. **Summary:** Each missing angle is found by subtracting the sum of known angles from 360°.