Question

42 х квадрат - 71х + 30 = 0

Answer 1

42x²-71x+30=0
D=(-71)²-4*30*42=5041-5040=1=1²
$x_{1}= frac{-(-71)- sqrt{1} }{2*42} = frac{71-1}{84} = frac{70}{84} = frac{5}{6} \ x_{2}= frac{-(-71)+ sqrt{1} }{2*42} = frac{71+1}{84} = frac{72}{84} = frac{6}{7}$