can someone help me with this?

Yea, sure thing...
So like, in a quadrilateral the sum of its angles will form 360°.
So,
(2x - 16)° + 2x° + x° + (x + 10)° = 360°
2x - 16 + 2x + x + x + 10 = 360
2x + 2x + x + x - 16 + 10 = 360
6x - 6 = 360
6x = 360 + 6
6x = 366
x = 366 ÷ 6
x = 61.
m<R = 2x° = 2 × 61 = 122°.
Hope it helps ya mate :))