Question

pergunta nas fotos?
obs calculo?

Answer 1

a) x² - 3x - 40 = 0

a= 1
b= -3
c= -40

Δ= (-3)² - 4 . 1 . (-40)
Δ= 9 + 160
Δ= 169

x = $\frac{- (-3) +- \sqrt{169}}{2.1}$
x¹ = $\frac{3+13}{2} = 8$
x² = $\frac{3-13}{2} = -5$

-x² + 5x - 6 = 0

a= -1
b= 5
c= -6

Δ= 5² - 4 .(-1) . (-6)
Δ= 25 - 24
Δ= 1

x= $\frac{-5+- \sqrt{1}}{2.(-1)}$
x¹= $\frac{-5+1}{-2} = 2$
x²= $\frac{-5-1}{-2} = 3$

:)