1. **Stating the problem:**
We have three vase-like shapes with given surface areas, volumes, and heights. We want to analyze the first shape (A) which has a surface area of 50 cm² and a height of 5 cm.
2. **Formula and rules:**
For 3D shapes like vases, surface area (SA) and volume (V) depend on the shape's geometry. Since the exact shape is not specified, we assume it is a cylinder-like shape for simplicity.
- Surface area of a cylinder: $$SA = 2\pi r^2 + 2\pi r h$$
- Volume of a cylinder: $$V = \pi r^2 h$$
3. **Given:**
- Surface area $$SA = 50$$ cm²
- Height $$h = 5$$ cm
4. **Find the radius $$r$$:**
Using the surface area formula,
$$50 = 2\pi r^2 + 2\pi r \times 5$$
5. **Simplify:**
$$50 = 2\pi r^2 + 10\pi r$$
6. **Divide both sides by $$2\pi$$ to simplify:**
$$\frac{50}{2\pi} = r^2 + 5r$$
Intermediate step with cancellation:
$$\frac{\cancel{50}}{\cancel{2}\pi} = r^2 + 5r$$
Calculate $$\frac{50}{2\pi} = \frac{25}{\pi} \approx 7.96$$
7. **Rewrite the quadratic equation:**
$$r^2 + 5r - 7.96 = 0$$
8. **Solve quadratic using the formula:**
$$r = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$ where $$a=1$$, $$b=5$$, $$c=-7.96$$
Calculate discriminant:
$$\Delta = 5^2 - 4 \times 1 \times (-7.96) = 25 + 31.84 = 56.84$$
Calculate roots:
$$r = \frac{-5 \pm \sqrt{56.84}}{2} = \frac{-5 \pm 7.54}{2}$$
9. **Select positive root:**
$$r = \frac{-5 + 7.54}{2} = \frac{2.54}{2} = 1.27$$ cm
10. **Final answer:**
The radius of the vase is approximately $$1.27$$ cm.
This completes the solution for the first vase (A).
Vase Radius 8A1B2C
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.