Solve Exponents 2Abb0D
1. **State the problem:**
We are given the system of equations:
$$3^x + y = \sqrt[3]{27}$$
$$4^y \div 2^x = 8$$
We need to find the values of $x$ and $y$.
2. **Simplify the constants:**
$$\sqrt[3]{27} = 3$$ because $3^3 = 27$.
So the first equation becomes:
$$3^x + y = 3$$
3. **Rewrite the second equation:**
Recall that $4 = 2^2$, so:
$$4^y = (2^2)^y = 2^{2y}$$
The second equation is:
$$\frac{4^y}{2^x} = 8$$
Substitute:
$$\frac{2^{2y}}{2^x} = 8$$
Using the law of exponents:
$$2^{2y - x} = 8$$
Since $8 = 2^3$, we have:
$$2^{2y - x} = 2^3$$
Therefore:
$$2y - x = 3$$
4. **Rewrite the first equation:**
$$3^x + y = 3$$
We want to express $y$ in terms of $x$:
$$y = 3 - 3^x$$
5. **Substitute $y$ into the second equation:**
$$2(3 - 3^x) - x = 3$$
Simplify:
$$6 - 2 \cdot 3^x - x = 3$$
Bring all terms to one side:
$$6 - 2 \cdot 3^x - x - 3 = 0$$
$$3 - 2 \cdot 3^x - x = 0$$
6. **Solve for $x$:**
Try integer values for $x$:
- For $x=0$:
$$3 - 2 \cdot 3^0 - 0 = 3 - 2 - 0 = 1 \neq 0$$
- For $x=1$:
$$3 - 2 \cdot 3^1 - 1 = 3 - 6 - 1 = -4 \neq 0$$
- For $x=2$:
$$3 - 2 \cdot 3^2 - 2 = 3 - 18 - 2 = -17 \neq 0$$
- For $x=-1$:
$$3 - 2 \cdot 3^{-1} - (-1) = 3 - 2 \cdot \frac{1}{3} + 1 = 3 - \frac{2}{3} + 1 = \frac{10}{3} \neq 0$$
- For $x=3$:
$$3 - 2 \cdot 3^3 - 3 = 3 - 54 - 3 = -54 \neq 0$$
Try $x=1.5$:
$$3 - 2 \cdot 3^{1.5} - 1.5$$
Calculate $3^{1.5} = 3^{1 + 0.5} = 3 \times \sqrt{3} \approx 3 \times 1.732 = 5.196$
So:
$$3 - 2 \times 5.196 - 1.5 = 3 - 10.392 - 1.5 = -8.892 \neq 0$$
Try $x=0.5$:
$$3 - 2 \times 3^{0.5} - 0.5 = 3 - 2 \times 1.732 - 0.5 = 3 - 3.464 - 0.5 = -0.964 \neq 0$$
Try $x=0.3$:
$$3 - 2 \times 3^{0.3} - 0.3$$
Calculate $3^{0.3} = e^{0.3 \ln 3} \approx e^{0.329} = 1.39$
So:
$$3 - 2 \times 1.39 - 0.3 = 3 - 2.78 - 0.3 = -0.08 \approx 0$$
Try $x=0.25$:
$$3 - 2 \times 3^{0.25} - 0.25$$
Calculate $3^{0.25} = e^{0.25 \ln 3} \approx e^{0.274} = 1.315$
So:
$$3 - 2 \times 1.315 - 0.25 = 3 - 2.63 - 0.25 = 0.12 \neq 0$$
By interpolation, $x \approx 0.28$.
7. **Find $y$:**
$$y = 3 - 3^x \approx 3 - 3^{0.28}$$
Calculate $3^{0.28} = e^{0.28 \ln 3} \approx e^{0.307} = 1.36$
So:
$$y \approx 3 - 1.36 = 1.64$$
**Final answer:**
$$x \approx 0.28, \quad y \approx 1.64$$