Question

a)x la a 2 a-13x+12=0...b)x la a 2 a -16x+15=0...c)2x la a 2 a-14x+12=0

Answer 1

a). Δ=b²-4ac
Δ=(13)²-4x1x12=169-48=121
x1=$\frac{-13- \sqrt{121} }{2*1} = \frac{-13-11}{2} = \frac{-24}{2} =-12$
x2=$\frac{-13+11}{2*1} = \frac{2}{2} =1$
b). Δ=(-16)²-4*1*15=256-60=196
x1=$\frac{16-14}{2} = \frac{2}{2} =1$
x2=$\frac{16+14}{2} = \frac{30}{2} =15$
c).Δ=(-14)²-4*2*12=196-96=100
X1=$\frac{14-10}{2*2} = \frac{4}{4} =1$
X2=$\frac{14+10}{2*2} = \frac{24}{4} =6$