Mister Exam
Other calculators
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How to use it?
- Equation:
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Equation (x-3)*(x+4)=0
-
Equation tg(x)=-1
-
Equation x^2+5x-14=0
- Equation (m+8)*(m-7)=0
- Express {x} in terms of y where:
- 20*x+6*y=8
- -1*x-17*y=-12
- -16*x-20*y=6
- (x^2+y^2-1)^3-x^2*y^3=0
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Identical expressions
- (m+ eight)*(m- seven)= zero
- (m plus 8) multiply by (m minus 7) equally 0
- (m plus eight) multiply by (m minus seven) equally zero
- (m+8)(m-7)=0
- m+8m-7=0
- (m+8)*(m-7)=O
-
Similar expressions
- (m-8)*(m-7)=0
- 43*m-(m+8*m-76)/(9+48)=84
- (m+8)*(m+7)=0
(m+8)*(m-7)=0 equation
The teacher will be very surprised to see your correct solution 😉
The solution
Detail solution
Expand the expression in the equation
$$\left(m - 7\right) \left(m + 8\right) = 0$$
We get the quadratic equation
$$m^{2} + m - 56 = 0$$
This equation is of the form
A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$m_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$m_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 1$$
$$b = 1$$
$$c = -56$$
, then
Because D > 0, then the equation has two roots.
or
$$m_{1} = 7$$
$$m_{2} = -8$$
$$\left(m - 7\right) \left(m + 8\right) = 0$$
We get the quadratic equation
$$m^{2} + m - 56 = 0$$
This equation is of the form
a*m^2 + b*m + c = 0
A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$m_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$m_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 1$$
$$b = 1$$
$$c = -56$$
, then
D = b^2 - 4 * a * c =
(1)^2 - 4 * (1) * (-56) = 225
Because D > 0, then the equation has two roots.
m1 = (-b + sqrt(D)) / (2*a)
m2 = (-b - sqrt(D)) / (2*a)
or
$$m_{1} = 7$$
$$m_{2} = -8$$
Sum and product of roots
[src]
sum
-8 + 7
$$-8 + 7$$
=
-1
$$-1$$
product
-8*7
$$- 56$$
=
-56
$$-56$$
-56