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Identify the roots of gx= x2+3x-4 x^2-4x+29

1 Answer

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Answer:

x1=1

x2= -4

x3= (2 + 5i)

x4= (2 - 5i)

Explanation:

STEP 1-

Find the roots of the first term.

(x^2 + 3x -4)=0

Then group the terms that contain the same variable, and move the constant to the opposite side of the equation.

(x^2 + 3x)=4

Complete the square. Remember to balance the equation by adding the same constants to each side.

(x^2 + 3x + 1.5^2)=4 + 1.5^2

(x^2 + 3x + 1.5^2)=6.25

Rewrite as perfect squares

(x + 1.5)^2=6.25

Square root both sides.

(x + 1.5) = (+/-)2.5

x= -1.5(+/-)2.5

x= -1.5 + 2.5 = 1

x= -1.5 + 2.5= -4

so the factored form of the first term.

(x^2 + 3x + 4) = (x - 1) (x + 4)

STEP 2-

Find the roots of the second term

(x^2 - 4x + 29)= 0

Group terms that contain the same variable, and move the constant to the opposite side of the equation

(x^2 - 4x)= -29

Complete the square. Remember to balance the equation by adding the same constants to each side

(x^2 - 4x + 4) = - 29 + 4

(x^2 -4x + 4) = -25

Rewrite as perfect squares

(x - 2)^2 = -25

Remember that

i = square root of -1

Square root both sides

(x - 2) = (+/-)5i

x= 2 (+/-)5i

x= 2 + 5i

x= 2 - 5i

so the factored form of the second term is

(x^2 - 4x + 29) = (x - (2 + 5i))(x - (2 - 5i))

STEP 3-

Substitute the factored form of the first and second term in g(x)

g(x) = (x-1)(x + 4)(x- (2+ 5i))(x- ( 2-5i)

there for you have your answers

User Swagata Prateek
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