Equação 2 grau me ajude
Soluções para a tarefa
a) x² - 6x + 8 = 0
Δ = b² - 4.a.c x = -b ±√Δ / 2. a
Δ = (-6)² - 4. 1 . 8 x = 6 ± 2/ 2. 1
Δ = 36 - 32 x1 = 6 + 2/ 2 x2 = 6 - 2/2
Δ = 4 x1 = 8/2 x2 = 4/2
x1 = 4 x2 = 2
b) x² - 4x + 3 = 0
Δ = b² - 4.a.c x = -b ±√Δ / 2. a
Δ = (-4)² - 4.1.3 x = 4 ± √4/ 2.1
Δ = 16 - 12 x1 = 4 + 2/2 x2 = 4 - 2/2
Δ = 4 x1 = 6/2 x2 = 2/2
x1 = 3 x2 = 1
c) x² - 15x + 50 = 0
Δ = b² - 4.a.c x = -b ±√Δ / 2. a
Δ = (-15)² - 4. 1 . 50 x = 15 ±√25/ 2.1
Δ = 225 - 200 x = 15 ± 5/2
Δ = 25 x1 = 15 + 5/2 x2 = 15 - 5/2
x1 = 20/2 x2 = 10/2
x1 = 10 x2 = 5
d) x² + x - 2 = 0
Δ = b² - 4.a.c x = -b ±√Δ / 2. a
Δ = 1² - 4 . 1 . -2 x = -1 ±√9 / 2.1
Δ = 1 + 8 x = -1 ± 3/ 2
Δ = 9 x1 = -1 + 3/2 x2 = -1 - 3/2
x1 = 2/2 x2 = -4/2
x1 = 1 x2 = -2
e) x² + x - 12 = 0
Δ = b² - 4.a.c x = -b ±√Δ / 2. a
Δ = 1² - 4 . 1 - 12 x = -1 ±√49 / 2.1
Δ = 1 + 48 x = -1 ± 7/ 2
Δ = 49 x1 = -1 + 7/2 x2 = -1 - 7/2
x1 = 6/2 x2 = -8/2
x1 = 3 x2 = -4
f) x² + 3x + 2 = 0
Δ = b² - 4.a.c x = -b ±√Δ / 2. a
Δ = 3² - 4 . 1 . 2 x = -3 ±√1 / 2.1
Δ = 9 - 8 x = -3 ± 1/ 2
Δ = 1 x1 = -3 + 1/2 x2 = -3 - 1/2
x1 = -2/2 x2 = -4/2
x1 = -1 x2 = -2
g) x² + 9x + 20 = 0
Δ = b² - 4.a.c x = -b ±√Δ / 2. a
Δ = 9² - 4 . 1 . 20 x = -9 ±√1 / 2.1
Δ = 81 - 80 x = -9 ± 1/ 2
Δ = 1 x1 = -9 + 1/2 x2 = -9 - 1/2
x1 = -8/2 x2 = -10/2
x1 = -4 x2 = -5
h) x² + 8x + 7 = 0
Δ = b² - 4.a.c x = -b ±√Δ / 2. a
Δ = 8² - 4 . 1 . 7 x = -8 ±√36 / 2.1
Δ = 64 - 28 x = -8 ± 6/ 2
Δ = 36 x1 = -8 + 6/2 x2 = -8 - 6/2
x1 = -2/2 x2 = -14/2
x1 = -1 x2 = -7
i) x² - 7x - 30 = 0
Δ = b² - 4.a.c x = -b ±√Δ / 2. a
Δ = (-7)² - 4 . 1 . -30 x = 7 ±√169 / 2.1
Δ = 49 + 120 x = 7 ± 3/ 2
Δ = 169 x1 = 7 + 3/2 x2 = 7 - 3/2
x1 = 10/2 x2 = 4/2
x1 = 5 x2 = 2