Mister Exam
Other calculators
-
How to use it?
- Equation:
-
Equation x^2+7=0
-
Equation x+2=0
-
Equation 2x=0
-
Equation (x-1)(-x-4)=0
- Express {x} in terms of y where:
- -15*x-13*y=-20
- -15*x-19*y=2
- 4*x+4*y=13
- -4*x+14*y=-2
-
Identical expressions
- (x- one)(-x- four)= zero
- (x minus 1)( minus x minus 4) equally 0
- (x minus one)( minus x minus four) equally zero
- x-1-x-4=0
- (x-1)(-x-4)=O
-
Similar expressions
- (x-1)*(-x-4)=0
- (x-1)(-x+4)=0
- (x+1)(-x-4)=0
- (3x-1)(-x-4)=v
- (x-1)(x-4)=0
(x-1)(-x-4)=0 equation
The teacher will be very surprised to see your correct solution 😉
The solution
Detail solution
Expand the expression in the equation
$$\left(- x - 4\right) \left(x - 1\right) = 0$$
We get the quadratic equation
$$- x^{2} - 3 x + 4 = 0$$
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
$$a = -1$$
$$b = -3$$
$$c = 4$$
, then
Because D > 0, then the equation has two roots.
or
$$x_{1} = -4$$
$$x_{2} = 1$$
$$\left(- x - 4\right) \left(x - 1\right) = 0$$
We get the quadratic equation
$$- x^{2} - 3 x + 4 = 0$$
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
$$a = -1$$
$$b = -3$$
$$c = 4$$
, then
D = b^2 - 4 * a * c =
(-3)^2 - 4 * (-1) * (4) = 25
Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
or
$$x_{1} = -4$$
$$x_{2} = 1$$
The graph