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- Equation:
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Equation (x-1)(x+9)=8x
- Equation (49^sinx)^cosx=7^(sqrt3)^sinx
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Equation sin(6*x)+cos(6*x)*sqrt(3)=-2*cos(8*x)
- Equation 72:(x-3)-72:(x+3)=2
- Express {x} in terms of y where:
- -1*x-19*y=-10
- 5*x+5*y=20
- 4*x-16*y=6
- sqrt(x^2+y^2+4x-6y-12)+(x^2+10x-27)=8-|y-9|+|y-3|
- Integral of d{x}:
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8x
- Derivative of:
- 8x
- Graphing y =:
- 8x
-
Identical expressions
- (x- one)(x+ nine)=8x
- (x minus 1)(x plus 9) equally 8x
- (x minus one)(x plus nine) equally 8x
- x-1x+9=8x
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Similar expressions
- sin((pi*(8*x+5)/6))=sqrt(3)/2
- (x+1)(x+9)=8x
- (x-1)(x-9)=8x
- (x-1)*(x+9)=8x
- sin(6*x)+cos(6*x)*sqrt(3)=-2*cos(8*x)
(x-1)(x+9)=8x equation
The teacher will be very surprised to see your correct solution 😉
The solution
Detail solution
Move right part of the equation to
left part with negative sign.
The equation is transformed from
$$\left(x - 1\right) \left(x + 9\right) = 8 x$$
to
$$- 8 x + \left(x - 1\right) \left(x + 9\right) = 0$$
Expand the expression in the equation
$$- 8 x + \left(x - 1\right) \left(x + 9\right) = 0$$
We get the quadratic equation
$$x^{2} - 9 = 0$$
This equation is of the form
A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 1$$
$$b = 0$$
$$c = -9$$
, then
Because D > 0, then the equation has two roots.
or
$$x_{1} = 3$$
$$x_{2} = -3$$
left part with negative sign.
The equation is transformed from
$$\left(x - 1\right) \left(x + 9\right) = 8 x$$
to
$$- 8 x + \left(x - 1\right) \left(x + 9\right) = 0$$
Expand the expression in the equation
$$- 8 x + \left(x - 1\right) \left(x + 9\right) = 0$$
We get the quadratic equation
$$x^{2} - 9 = 0$$
This equation is of the form
a*x^2 + b*x + c = 0
A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 1$$
$$b = 0$$
$$c = -9$$
, then
D = b^2 - 4 * a * c =
(0)^2 - 4 * (1) * (-9) = 36
Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
or
$$x_{1} = 3$$
$$x_{2} = -3$$
The graph