The image contains several math problems related to equations of circles and graphs. Let's go through each one and solve them.

4. Dapatkan persamaan dari

(a) Setengah bagian yang bawah dari lingkaran $x^2 + y^2 = 16$

• The equation $x^2 + y^2 = 16$ represents a circle centered at the origin $(0, 0)$ with a radius of 4.
• "Setengah bagian yang bawah" means the lower half of the circle, which corresponds to the values where $y \leq 0$.
• Therefore, the equation is: $y = -\sqrt{16 - x^2}$

(b) Setengah bagian yang atas dari lingkaran $x^2 + y^2 + 2x - 4y + 1 = 0$

• First, complete the square for the given equation $x^2 + y^2 + 2x - 4y + 1 = 0$. $(x^2 + 2x) + (y^2 - 4y) = -1$ Complete the square: $(x+1)^2 - 1 + (y-2)^2 - 4 = -1$ Simplify to: $(x+1)^2 + (y-2)^2 = 4$ This is a circle centered at $(-1, 2)$ with radius 2.
• "Setengah bagian yang atas" means the upper half, so the equation is: $y = 2 + \sqrt{4 - (x+1)^2}$

5. Dapatkan persamaan dari

(a) Setengah bagian yang kanan dari lingkaran $x^2 + y^2 = 9$

• The equation $x^2 + y^2 = 9$ represents a circle centered at the origin with radius 3.
• "Setengah bagian yang kanan" refers to the right half, corresponding to $x \geq 0$.
• The equation for the right half is: $x = \sqrt{9 - y^2}$

(b) Setengah bagian yang kiri dari lingkaran $x^2 + y^2 - 4x + 3 = 0$

• First, complete the square: $(x^2 - 4x) + y^2 = -3$ Complete the square: $(x-2)^2 - 4 + y^2 = -3$ Simplify to: $(x-2)^2 + y^2 = 1$ This is a circle centered at $(2, 0)$ with a radius of 1.
• "Setengah bagian yang kiri" refers to the left half, corresponding to $x \leq 2$.
• The equation for the left half is: $x = 2 - \sqrt{1 - y^2}$

6. Gambarkan grafik

(a) $y = \sqrt{25 - x^2}$

• This equation represents the upper half of a circle centered at the origin with radius 5.

(b) $y = \sqrt{5x - 4x - 2}$

• The expression under the square root simplifies to $y = \sqrt{x(5 - 4) - 2} = \sqrt{x - 2}$.
• This is the graph of the square root function, starting at $x = 2$.

7. Gambarkan grafik

(a) $x = \sqrt{4 - y^2}$

• This represents the right half of a circle centered at the origin with radius 2.

(b) $x = 3 + \sqrt{4 - y^2}$

• This represents the right half of a circle centered at $(3, 0)$ with radius 2.

Would you like more details on any of these problems or have any specific questions?

Here are five related questions that could expand your understanding:

1. How do you find the radius of a circle from its equation?
2. What does completing the square mean, and how is it applied to conic sections?
3. How can you determine which part of a circle's equation represents the left, right, upper, or lower half?
4. How do you derive the equation of a circle given the endpoints of a diameter?
5. How can you graph the equation $y = \sqrt{16 - x^2}$ manually?

Tip: Always check if you need to complete the square when dealing with circle equations that aren't in standard form.