Question 363506
The diagonal brace ,the horizontal & vertical support form a right angle
let height be x
horizontal distance = x+30
the brace is the diagonal
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apply pythagoras theorem

x^2+(x+30)^2=150^2
x^2+x^2+60x+900=22500
2x^2+60x+900-22500=0
2x^2+60x-21600=0
/2
x^2+30x-10800=0
x^2+120x-90x-10800=0
x(x+120)-90(x+120)=0
(x+120)(x-90)=0
x=90 the positive value.
90 ft  height & 120 ft horizontal span
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m.ananth@hotmail.ca