Find x-intercept?

Question

I need to find the x-intercept , but I can't factor this one -2x^2 - 12x -14, so what I need to do now ? Can somebody help me? Plz

Answer 1

Common factor first

2x² - 12x - 14

2(x² - 6x - 7)

The middle term inside the parenthesis is - 6x

find the sum of the middle term

x = 1

Multiply the the first term 1 by the last term 7 equals 7 and factor

factors of 7 =

1 x 7

+ 1 and - 7 satisfy the sum of the middle term

since 1 = x

Insert + x and - 7x into the equation

2(x² - 6x - 7)

Group factor inside the parenthesis

2(x² + x - 7x - 7)

2[x(x + 1) -7(x + 1)]

2(x - 7)(x + 1)

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roots

2 = 0

Roots

x - 7 = 0

x - 7 + 7 = 0 + 7

x = 7

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Roots

x + 1 = 0

x + 1 - 1 + 0 - 1

x = - 1

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The x values or roots is called solutions to the equation.

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Answer 2

f(x) = -2x^2 - 12x -14
f(x) = -2 (x^2 + 6x + 7)

-b +/- √(b² - 4ac) all over 2a
-6 +/- √(6² - 4*1*7) all over 2*1
-6 +/- √(36 - 28) all over 2
-6 +/- √8 all over 2
-6 +/- 2√2 all over 2
-3 +/- √2
-3 + √2, -3 - √2

Answer 3

2(x-1)-2(6x-7)

Both of the 2's cancel out.

x=1 and x= 7/6

I hope its right since you didnt write the problem correctly.

Answer 4

-2(x^2+6x+7)

Answer 5

set it equal to zero and use quadratic formula

x= (12 +/-sqrt(144-112))/-4
x= (12+/- sqrt 32)/-4
x= (12 +5.657)/-4 = -4.414
x= (12 -5.657)/-4 = -1.586