Question

if (x^2+1/x^2)-4(x+1/x)+23/4=0 , find (x+1/x)​

Answer 1

Answer:

Given systems of equations are:

2

x

−

3

y

+4=0 ....(1)

2

x

−

3

5y

+12=0 ...(2)

Now from eq1 and eq2 will get:

3x−2y+24 ...(3)

3x−10y+72 ...(4)

To solve this pair of equations for x and y using cross-multiplication, we arrange the variables x and y and their coefficients a1, a2, b1 and b2, and the constants c1 and c2 as:

x=

a

1

b

2

−a

2

b

1

b

1

c

2

−b

2

c

1

y=

a

1

b

2

−a

2

b

1

c

1

a

2

−c

2

a

1

⇒x=

(3×10)−(3×−2)

(−2×72)−(−10×24)

⇒y=

(3×10)−(3×−2)

(24×3)−(72×3)

⇒x=

−30−(−6)

−144−(240)

⇒x=

−24

96

=−4

⇒y=

−30−(−6)

72−216

⇒y=

−24

−144

=6

⇒x=−4,y=6

x+y= 6−4=2