Question

resolva a equação 2x²-7x=15

Answer 1

I) 2x² -7x - 15 = 0, a = 2, b = -7 e c = - 15

Δ = b² - 4.a.c

Δ= (-7)² - 4.2.-15

Δ = 49 + 120

Δ = 169

II) X' = - b +√Δ / 2.a

Obs> √169 = 13

x' = \frac{-(-7)+13}{2.2}

x'= \frac{20}{4} = 5

X'' = -b -√Δ/2a

X'' = \frac{7-13}{2.2} = \frac{-6}{4}= \frac{-3}{2}

Answer 2

2x²-7x-15=0

b²-4ac

(-7)² -4 . 2 . -15

49 + 120

delta = 169

x = -b -+ √delta

---------------

2a

7 -+√169

--------------

4

7-+13 => x´ = 20 =5 x´ ´ = 6 = 1,5

------- ---- ----

4 4 4