Triangle ABC v2

Area of the triangle is 12 cm square. Angle ACB = 30º , AC = (x + 2) cm, BC = x cm. Calculate the value of x.

Correct answer:

x =  -8 cm

Step-by-step explanation:

S=12 sin30=h/x h=xsin(30) S=1/2(x+2)h S=1/2(x+2)x.sin(30) 12=1/2 0.5 x(x+2) 12=1/20.5x(x+2)  12=1/2 0.5 x (x+2) 0.25x20.5x+12=0 0.25x2+0.5x12=0  a=0.25;b=0.5;c=12 D=b24ac=0.5240.25(12)=12.25 D>0  x1,2=b±D2a=0.5±12.250.5=1±49 x1,2=1±7 x1=6 x2=8   Factored form of the equation:  0.25(x6)(x+8)=0 x>0,x>2 x=x2=(8)=8 cm

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