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by transposing-36 and 2bx, it becomes 3ax-2bx=3b,

by collecting the coefficients of x, we shall have

(3α-2b)=3b,

by division, x

3b

3a -26

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$200. Now, if in this example, we suppose 3a-2b=

36

0,or 3a=26, then x; which shows that in the above equality such a relation cannot exist between the quantities a and b, or if there should, the equality cannot take place.

Let us, in order to see what would be the result,

3a

substitute for 6 in equation (1), and it becomes

2

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multiplying by 2, we shall have

• 6ax-9a+8a-18ax-12ax+8a, by transposition, 18ax-18ax-Ja,

...0=9a.

Which is evidently absurd, in all cases, except that a 0. and therefore b=0, and then the original equation is nothing else than 0-0 in its primitive state.

We may therefore conclude that there is no finite value, which, when substituted for x in the primitive equation, would fulfil the condition_required, this may be better verified by a numerical example, Thus, let a 4, and 6-6; then substituting these b=6; values for a and b in the given equation, it becomes

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Ex. 11. Given 2ax+b=3cx+4a, to find the va

lue of x.

by transposition, 2ax-3cx-4a-b,

by collecting the coefficients, (2a-3c)x-4a-b,

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2a-3c

201. Here, if 4a=b, and at the same time, 2a> or <3c; then x=0.

For a=1,b=4 and c=1, then, the above equation becomes

2x-x-4-4, .. x= 0. Or, substituting these values of a, b, and c, in the formula,

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Again, if 4a-b-0, and 2a-3c=0; then

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4a-b 0

2a-3c 0

which is the mark of indetermination, or, which is the same thing, we learn from this result, that the value of x may be any number, either positive or negative, from nought to infinity, and both inclusively.

In order to illustrate this, let a=3, b=12, and =2; then

30:

4a-b 12-12 2-2 0

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Now, let us resume the given equation, and by substituting these values of a, b, and c, we shall have

6x+12=6x+12, ... 6x=6x. But this is what Analysts call an identical equation; where it evidently appears that x is indeterminate, or that any quantity whatever may be substituted for it.

Ex. 12. Given 19x+13-59-4x, to find the value of x.

by transposition, 19x+4x=59-13,
or, 23x=46;
.. by division, x=2.

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Ex. 13. Given 3x+4- =46—2x, to find the

value of x.

3

Multiplying both sides by 3,

9x+12-x=138-6x,

by transposition, 9x+6x-x-138-12,

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Ex. 14. Given x2+15x=35x-3x2, to find the

value of x.

Dividing every term by x,

x+15=35-3x,

by transposition, x+3x=35-15,

or 4x=20;

.*. x=5.

Ex. 15. Given +10=3+11, to find the

value of x.

x

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6

4

Here 12 is the least common multiple of 6, 4, 3, and 2;

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... multiplying both sides of the equation by 12, 2x-3x+120=4x-6x+132;

by transposition, 2x-3x-4x+6x=132-120,

or 8x-7x=12;

... x=12.

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3x+9

Ex. 17. Given

+6=

to

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2

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* Ex. 28. Given (2x+8)=4x2+14x+172, to find

Ans. x=

=1.

18- -X

:: 7: 4, to find the

2

4

value of x.

Ans. x=2.

the value of x.

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Ex. 29. Given

+2x=

+16, to find

5

5

the value of x.

2

x2 x

Ans. x=7.

Ex. 30. Given 7+4=3x-118x+15

find the value of x.

Ex. 31. Given +

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2

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of x.

Ans. x=

3a 1

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