Please help me solve this simultaneous equation:
Write two separate equations:
Use this principle to rewrite each:
can be rewritten as
Rewriting the first:
Rewriting the second:
Now rewrite as
or, multiplying exponents:
So now we have this system:
Using the second, we can substitute
for in the first:
Get 0 on the left
Factor the right side:
Using the zero factor principle,
gives
gives
So there is only one value for ,
which is
Substitute for x in
Now we use the rule:
Any number raised to the zero power,
except zero itself, equals 1
Thus
and the solution is ,
Let's check:
can be rewritten as which is true.
can be rewritten as which is also true.
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and another one:
When no base is written, the base is understood:
We can rewrite the first using the rule:
can be rewritten as
becomes
We can use this rule on the left side of the second eq:
becomes
Now we use the principle:
can be rewritten
So we have the system of ewquations:
Can you solve that system of equations by substitution?
If not post again asking how.
That last system of equations has two ordered pairs
of solutions:
(,)= (,) and (,) = (,)
However we must check them, because sometimes a solution
to our final equations is not a solution to the original
equation:
Checking (,)= (,) in the first equation:
Checking (,)= (,) in the second equation:
Since
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Checking (,)= (,) in the first equation:
Checking (,)= (,) in the second equation:
We can stop here because the first term is
undefined because the logarithm of a negative
number is not defined (except in certain
advanced mathematics, but never in
ordinary algebra)
So there is but one solution, (,)= (,)
Edwin