Math Problem Statement

Solve the exponential equations: 8^(x+3) = 22, 1.23^(x+4) = 35, 29(1.16)^(x-3) = 87, 8 + 8(1.12)^(2x) = 24.

Solution

The image contains four exponential equations to solve. Let's work through each one step by step, rounding the answers to three decimal places as requested.

1. 8x+3=228^{x+3} = 22

Taking the logarithm of both sides:

(x+3)log(8)=log(22)(x+3) \log(8) = \log(22)

Solve for xx:

x+3=log(22)log(8)x+3 = \frac{\log(22)}{\log(8)}

Then:

x=log(22)log(8)3x = \frac{\log(22)}{\log(8)} - 3

2. 1.23x+4=351.23^{x+4} = 35

Taking the logarithm of both sides:

(x+4)log(1.23)=log(35)(x+4) \log(1.23) = \log(35)

Solve for xx:

x+4=log(35)log(1.23)x+4 = \frac{\log(35)}{\log(1.23)}

Then:

x=log(35)log(1.23)4x = \frac{\log(35)}{\log(1.23)} - 4

3. 29(1.16)x3=8729(1.16)^{x-3} = 87

First divide both sides by 29:

(1.16)x3=8729(1.16)^{x-3} = \frac{87}{29}

Now take the logarithm of both sides:

(x3)log(1.16)=log(8729)(x-3) \log(1.16) = \log\left(\frac{87}{29}\right)

Solve for xx:

x3=log(8729)log(1.16)x-3 = \frac{\log\left(\frac{87}{29}\right)}{\log(1.16)}

Then:

x=log(8729)log(1.16)+3x = \frac{\log\left(\frac{87}{29}\right)}{\log(1.16)} + 3

4. 8+8(1.12)2x=248 + 8(1.12)^{2x} = 24

First, subtract 8 from both sides:

8(1.12)2x=168(1.12)^{2x} = 16

Divide both sides by 8:

(1.12)2x=2(1.12)^{2x} = 2

Now take the logarithm of both sides:

2xlog(1.12)=log(2)2x \log(1.12) = \log(2)

Solve for xx:

x=log(2)2log(1.12)x = \frac{\log(2)}{2\log(1.12)}

I will now calculate all values.Here are the solutions to the exponential equations, rounded to three decimal places:

  1. 8x+3=228^{x+3} = 22x=1.514x = -1.514
  2. 1.23x+4=351.23^{x+4} = 35x=13.174x = 13.174
  3. 29(1.16)x3=8729(1.16)^{x-3} = 87x=10.402x = 10.402
  4. 8+8(1.12)2x=248 + 8(1.12)^{2x} = 24x=3.058x = 3.058

Let me know if you would like more details on any of these steps.

Here are five related questions to consider:

  1. How do you solve exponential equations when both sides have different bases?
  2. What are the logarithmic properties useful for solving exponential equations?
  3. How can you verify the accuracy of an exponent found through logarithms?
  4. How are exponential and logarithmic functions inverses of each other?
  5. What happens if the base of the exponential equation is less than 1?

Tip: Always double-check your final answers by substituting them back into the original equations to confirm accuracy!

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Math Problem Analysis

Mathematical Concepts

Algebra
Exponential Equations
Logarithms

Formulas

log_b(a^x) = x log_b(a)
(b^x = a) -> (x = log_b(a))

Theorems

Logarithmic properties
Change of base formula

Suitable Grade Level

Grades 9-12