Resolva os problemas: a) x^2 - 10x + 25 = 0
b) x^2 - 4x - 5 = 0

(preciso da montagem da conta, junto com o resultado)

Step-by-step explanation:

a) x² - 10x + 25 = 0

(x-5)²=0

x-5=0

x=5

b) x² - 4x - 5 = 0

⇒ ( x 2 − 4 x + 4 ) − 5 − 4 = 0

⇒ ( x 2 − 4 x + 4 ) − 9 = 0

( x − 2 ) 2 − 9 = 0 ⇒

( x − 2 ) 2 = 9 ⇒

( x − 2 ) = ± √ 9 (don't forget the ± !) ⇒

x= − 1   x = 5

step-by-step explanation:

20% of 120 is 24. if you subtract 24 from 120 you get 96

can you put the picture up?

step-by-step explanation: