Mister Exam
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How to use it?
- Equation:
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Equation 2x+3=3(3x-5)+11x
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Equation 4(x-6)=7(x+9)
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Equation 40,5:x=-9
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Equation x^3+x-3=0
- Express {x} in terms of y where:
- 9*x+18*y=0
- -11*x+17*y=-17
- 16*x+6*y=3
- 13*x-15*y=-11
- Integral of d{x}:
- -9
- Limit of the function:
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-9
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Identical expressions
- forty , five :x=- nine
- 40,5:x equally minus 9
- forty , five :x equally minus nine
-
Similar expressions
- 40,5:x=+9
40,5:x=-9 equation
The teacher will be very surprised to see your correct solution 😉
The solution
Detail solution
Given the equation:
$$\frac{81}{2 x} = -9$$
Use proportions rule:
From a1/b1 = a2/b2 should a1*b2 = a2*b1,
In this case
so we get the equation
$$- \frac{2 x}{81} = \frac{1}{9}$$
$$- \frac{2 x}{81} = \frac{1}{9}$$
Divide both parts of the equation by -2/81
We get the answer: x = -9/2
$$\frac{81}{2 x} = -9$$
Use proportions rule:
From a1/b1 = a2/b2 should a1*b2 = a2*b1,
In this case
a1 = 1
b1 = 1/9
a2 = 1
b2 = -2*x/81
so we get the equation
$$- \frac{2 x}{81} = \frac{1}{9}$$
$$- \frac{2 x}{81} = \frac{1}{9}$$
Divide both parts of the equation by -2/81
x = 1/9 / (-2/81)
We get the answer: x = -9/2
Sum and product of roots
[src]
sum
-9/2
$$- \frac{9}{2}$$
=
-9/2
$$- \frac{9}{2}$$
product
-9/2
$$- \frac{9}{2}$$
=
-9/2
$$- \frac{9}{2}$$
-9/2
The graph