Firstly we calculate the height(h)...,
by using trigonometry ratios
;tan 45° = h/5
;where.. h = 5 tan 45°
;h = 5
Then we calculate the side x...using the height h and the angle of 30°
by also using trigonometry ratios
; sin 30° = 5/x
;where.. x = 5/(sin 30°)
Hence...., x = 10
Answer: x = 10