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Jack
10-10-2013, 12:28 PM
In the figure below what is the value of x given that 2x-y=110

44

Figure not drawn to scale

(A) 50

(B) 60

(C) 70

(D) 80

Thanks

miranda
10-10-2013, 12:32 PM
The sum of angles in a triangle is always 180^o

So, x+y+50=180 \Rightarrow x+y=130 (1)

2x-y=110 (2)

Solving the simultaneous equations (1), (2)

x+y=130 \Rightarrow x+2x-110=130 \Rightarrow 3x=240 \Rightarrow x=80^o

Therefore the correct answer is (D).

Jack
10-10-2013, 12:33 PM
thanks for your response!