7. Solve [tex]3^{2x+3}=243[/tex] for [tex]x[/tex].

A. [tex]x=\frac{2}{5}[/tex]
B. [tex]x=10[/tex]
C. [tex]x=2[/tex]
D. [tex]x=1[/tex]



Answer :

To solve the equation [tex]\(3^{2x+3} = 243\)[/tex] for [tex]\(x\)[/tex], let's follow a step-by-step approach.

1. Express 243 as a power of 3: To make the equation easier to handle, write 243 as a power of 3. We know that [tex]\(243 = 3^5\)[/tex], so we can rewrite the equation as:
[tex]\[ 3^{2x + 3} = 3^5 \][/tex]

2. Set the exponents equal to each other: Since the bases are the same (both are 3), we can set the exponents equal to each other:
[tex]\[ 2x + 3 = 5 \][/tex]

3. Solve for [tex]\(x\)[/tex]: Now, we solve the equation [tex]\(2x + 3 = 5\)[/tex] for [tex]\(x\)[/tex].

- Subtract 3 from both sides:
[tex]\[ 2x + 3 - 3 = 5 - 3 \][/tex]
Simplifying this gives:
[tex]\[ 2x = 2 \][/tex]

- Divide both sides by 2:
[tex]\[ \frac{2x}{2} = \frac{2}{2} \][/tex]
Simplifying this gives:
[tex]\[ x = 1 \][/tex]

So, the value of [tex]\(x\)[/tex] that satisfies the equation [tex]\(3^{2x+3} = 243\)[/tex] is [tex]\(x = 1\)[/tex].

The correct answer is:
D. [tex]\(x = 1\)[/tex]