Question

The quadratic formula gives which roots for the equation 2x^2+7x+-2

Answer 1

The quadratic expression is given
`2x^(2) +7x-2` where the constants are


`a=2`

`b=7`

`c=-2`

Quadratic formula to find the roots is given as

x₁,₂ = [-b plus minus √(b)²-4ac)] ÷ 2a

Substitute a, b, and c from our expression we have

x₁,₂ = [-7 plus minus √(7)²-(4×2×-2)] ÷ 2(2)
x₁,₂ = [-7 plus minus√65] ÷ 4

from here we'll work out x₁ and x₂ separately

x₁ = (-7+√65) ÷ 4 = 0.266 (round to 3 dp)
x₂ = (-7-√65) ÷ 4 = -3.766 (round to 3 dp)