Question

Resposta  -x²+4x-4=0 E Da  -5x²+7x-2=0

Answer 1

$- x^{2} +4x-4=0= delta= b^{2} -4.a.c= delta= 4^{2} -4.(-1).(-4)= delta=16-16=0 x1=4-+ \sqrt{0} /2=2 x2=4-+ \sqrt{0} /2=2$


$-5X^{2} +7X-2=0= DELTA= b^{2} -4.a.c= delta= 7^{2} -4.(-2).(-5)= delta=49-40=9 x1= \frac{-5-+ \sqrt{9} }{2.5} = \frac{-5-3}{10} \frac{-8}{10}  x2= \frac{-5-+ \sqrt{9} }{2.5}= \frac{-5+3}{10} =-2/10=5$