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In Mathematics / High School | 2014-04-19

Solve for \( x \):

\[ 2x^2 + 4x - 16 = 0 \]

Asked by Sarah7143

Answer (3)

in order to solve it, we need find the zero of the polynomial.
we find the zero of the polynomial by splitting the middle term method
2x2 -+ 4x - 16
= 2x2 + 8x - 4x -16
= 2x( x + 4)- 4(x + 4) = (2x-)(x+4)
we find the zeroes of the factors
experimentally we find two values, 2 and -4.
Thus, values of x are 2 and -4

Answered by tadvisohil886 | 2024-06-10

2 x 2 + 4 x − 16 = 0 / : 2 x 2 + 2 x − 8 = 0 ( ∗ ) x 2 + 2 x ⋅ 1 + 1 2 ​ ​ − 1 2 − 8 = 0 ( x + 1 ) 2 − 1 − 8 = 0 ( x + 1 ) 2 − 9 = 0 ( x + 1 ) 2 = 9 ⟺ x + 1 = − 3 or x + 1 = 3 x = − 3 − 1 or x = 3 − 1 x = − 4 or x = 2 ( ∗ ) ( a + b ) 2 = a 2 + 2 ab + b 2
0\ then\ x_1=\frac{-b-\sqrt\Delta}{2a}\ and\ x_2=\frac{-b+\sqrt\Delta}{2a}\\\\\Delta=2^2-4\cdot1\cdot(-8)=4+32=36;\ \sqrt\Delta=\sqrt{36}=6\\\\x_1=\frac{-2-6}{2\cdot1}=\frac{-8}{2}=-4;\ x_2=\frac{-2+6}{2\cdot1}=\frac{4}{2}=2"> 2 x 2 + 4 x − 16 = 0 / : 2 x 2 + 2 x − 8 = 0 a = 1 ; b = 2 ; c = − 8 Δ = b 2 − 4 a c i f Δ > 0 t h e n x 1 ​ = 2 a − b − Δ ​ ​ an d x 2 ​ = 2 a − b + Δ ​ ​ Δ = 2 2 − 4 ⋅ 1 ⋅ ( − 8 ) = 4 + 32 = 36 ; Δ ​ = 36 ​ = 6 x 1 ​ = 2 ⋅ 1 − 2 − 6 ​ = 2 − 8 ​ = − 4 ; x 2 ​ = 2 ⋅ 1 − 2 + 6 ​ = 2 4 ​ = 2

Answered by Anonymous | 2024-06-24

To solve the quadratic equation 2 x 2 + 4 x − 16 = 0 , we simplify and use the quadratic formula. The solutions are x = 2 and x = − 4 .
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Answered by tadvisohil886 | 2024-12-24