Mister Exam
Other calculators
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How to use it?
- Equation:
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Equation -20*(x-13)=-220
-
Equation x-x/12=55/12
-
Equation 3^x=81
-
Equation 12-x^2=11
- Express {x} in terms of y where:
- 18*x+19*y=7
- 16*x-15*y=4
- 1*x+6*y=6
- 20*x+9*y=17
- Derivative of:
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(x-7)^2
- Canonical form:
- (x-7)^2
-
Identical expressions
- (x- seven)^ two
- (x minus 7) squared
- (x minus seven) to the power of two
- (x-7)2
- x-72
- (x-7)²
- (x-7) to the power of 2
- x-7^2
-
Similar expressions
- (x+7)^2
(x-7)^2 equation
The teacher will be very surprised to see your correct solution 😉
The solution
Detail solution
Expand the expression in the equation
$$\left(x - 7\right)^{2} = 0$$
We get the quadratic equation
$$x^{2} - 14 x + 49 = 0$$
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
$$a = 1$$
$$b = -14$$
$$c = 49$$
, then
Because D = 0, then the equation has one root.
$$x_{1} = 7$$
$$\left(x - 7\right)^{2} = 0$$
We get the quadratic equation
$$x^{2} - 14 x + 49 = 0$$
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
$$a = 1$$
$$b = -14$$
$$c = 49$$
, then
D = b^2 - 4 * a * c =
(-14)^2 - 4 * (1) * (49) = 0
Because D = 0, then the equation has one root.
x = -b/2a = --14/2/(1)
$$x_{1} = 7$$