Mister Exam
Other calculators
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How to use it?
- Equation:
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Equation x^2+2x+1=0
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Equation cos(x/2)=1/2
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Equation (x+7)*(x-1)=0
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Equation -4/7*x^2+28=0
- Express {x} in terms of y where:
- -17*x+14*y=11
- -1*x-17*y=10
- 3*x+3*y=10
- 12*x+12*y=-3
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Identical expressions
- (x+ seven)*(x- one)= zero
- (x plus 7) multiply by (x minus 1) equally 0
- (x plus seven) multiply by (x minus one) equally zero
- (x+7)(x-1)=0
- x+7x-1=0
- (x+7)*(x-1)=O
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Similar expressions
- (x+7)(x-1)=0
- (x-7)*(x-1)=0
- (x+7)*(x+1)=0
- (x+7)*(x-16)^6/(x-15)^3=0
(x+7)*(x-1)=0 equation
The teacher will be very surprised to see your correct solution 😉
The solution
Detail solution
Expand the expression in the equation
$$\left(x - 1\right) \left(x + 7\right) = 0$$
We get the quadratic equation
$$x^{2} + 6 x - 7 = 0$$
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
$$a = 1$$
$$b = 6$$
$$c = -7$$
, then
Because D > 0, then the equation has two roots.
or
$$x_{1} = 1$$
$$x_{2} = -7$$
$$\left(x - 1\right) \left(x + 7\right) = 0$$
We get the quadratic equation
$$x^{2} + 6 x - 7 = 0$$
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
$$a = 1$$
$$b = 6$$
$$c = -7$$
, then
D = b^2 - 4 * a * c =
(6)^2 - 4 * (1) * (-7) = 64
Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
or
$$x_{1} = 1$$
$$x_{2} = -7$$
The graph