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Answer :

Answer:

x = - 2

Step-by-step explanation:

Given

[tex]2^{x+3}[/tex] × [tex]3^{x+4}[/tex] = 18 = 2 × 9 = [tex]2^{1}[/tex] × 3²

Then

[tex]2^{x+3}[/tex] = [tex]2^{1}[/tex]

Since bases on both sides are equal, both 2, then equate exponents

x + 3 = 1 ( subtract 3 from both sides )

x = - 2

Then

[tex]2^{-2+3}[/tex] = [tex]2^{1}[/tex]

and

[tex]3^{-2+4}[/tex] = 3²

18 = 2 × 3²

Answer:

x=-2

Step-by-step explanation:

[tex]2 {}^{x + 3} \times 3 {}^{x + 4 = 18} [/tex]

Apply the Inverse of the Product of Power Rule

If

[tex]x {}^{y} \times x {}^{z} = x {}^{y + z} [/tex]

This means that

[tex] {x}^{y + z} = {x}^{y} \times {x}^{z} [/tex]

So in order words,

[tex](2 {}^{x} \times 2 {}^{3} ) \times (3 {}^{x} \times 3 {}^{4} ) = 18[/tex]

[tex](2 {}^{x} \times 8) \times (3 {}^{x} \times 81) = 18[/tex]

Divide both sides by 31 and 8.

We get that

[tex]2 {}^{x} \times {3}^{x} = \frac{1}{36} [/tex]

[tex]6 {}^{x} = \frac{1}{36} [/tex]

Take the log of both sides.

[tex] log_{6}( \frac{1}{36} ) = x[/tex]

[tex]6 {}^{ - 2} = \frac{1}{36} [/tex]

so

[tex]x = - 2[/tex]

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