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Find the value of x for the given square.
(x^2- 4x)

Find the value of x for the given square. (x^2- 4x)-example-1
User Mayukh Bhattacharya
by
2.8k points

1 Answer

22 votes
22 votes

Answer:

x=2 √3 − 2 = 1.464101615

x=−2 √3 − 2 = −5.464101615

Explanation:


x^(2) + 4x=8

Subtract 8 from both sides of the equation.

x^2 + 4x − 8 = 8 − 8

Subtracting 8 from itself leaves 0.

x^2 +4x−8=0

This equation is in standard form: ax

2

+bx+c=0. Substitute 1 for a, 4 for b, and −8 for c in the quadratic formula,

2a

−b±

b

2

−4ac

.

x=

2

−4±

4

2

−4(−8)

Square 4.

x=

2

−4±

16−4(−8)

Multiply −4 times −8.

x=

2

−4±

16+32

Add 16 to 32.

x=

2

−4±

48

Take the square root of 48.

x=

2

−4±4

3

Now solve the equation x=

2

−4±4

3

when ± is plus. Add −4 to 4

3

.

x=

2

4

3

−4

Divide −4+4

3

by 2.

x=2

3

−2

Now solve the equation x=

2

−4±4

3

when ± is minus. Subtract 4

3

from −4.

x=

2

−4

3

−4

Divide −4−4

3

by 2.

x=−2

3

−2

The equation is now solved.

x=2

3

−2

x=−2

3

−2

Find the value of x for the given square. (x^2- 4x)-example-1
User Tropicalista
by
3.0k points