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Identical expressions
- (x- fourteen)(x+ twenty)= zero
- (x minus 14)(x plus 20) equally 0
- (x minus fourteen)(x plus twenty) equally zero
- x-14x+20=0
- (x-14)(x+20)=O
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Similar expressions
- (x+14)(x+20)=0
- (x-14)(x-20)=0
(x-14)(x+20)=0 equation
The teacher will be very surprised to see your correct solution 😉
The solution
Detail solution
Expand the expression in the equation
$$\left(x - 14\right) \left(x + 20\right) = 0$$
We get the quadratic equation
$$x^{2} + 6 x - 280 = 0$$
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
$$a = 1$$
$$b = 6$$
$$c = -280$$
, then
Because D > 0, then the equation has two roots.
or
$$x_{1} = 14$$
$$x_{2} = -20$$
$$\left(x - 14\right) \left(x + 20\right) = 0$$
We get the quadratic equation
$$x^{2} + 6 x - 280 = 0$$
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
$$a = 1$$
$$b = 6$$
$$c = -280$$
, then
D = b^2 - 4 * a * c =
(6)^2 - 4 * (1) * (-280) = 1156
Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
or
$$x_{1} = 14$$
$$x_{2} = -20$$
Sum and product of roots
[src]
sum
-20 + 14
$$-20 + 14$$
=
-6
$$-6$$
product
-20*14
$$- 280$$
=
-280
$$-280$$
-280