1. **Problem statement:** Find the value of $1 - 20 = \text{?}$ with options involving angles $30^\circ$, $90^\circ$, $60^\circ$.
Since the problem is unclear as written, we move to the next problem.
2. **Problem statement:** Given two complementary angles $x$ and $y$ with $\sin y = \frac{x}{5}$, find $\sin x$.
- Complementary angles satisfy $x + y = 90^\circ$.
- Using the identity $\sin y = \cos x$ because $y = 90^\circ - x$.
So, $\sin y = \cos x = \frac{x}{5}$.
We want $\sin x$.
Since $\sin^2 x + \cos^2 x = 1$, then
$$\sin x = \sqrt{1 - \cos^2 x} = \sqrt{1 - \left(\frac{x}{5}\right)^2}.$$
But $x$ is an angle, so $\frac{x}{5}$ is not a number unless $x$ is numeric. The problem likely means $\sin y = \frac{x}{5}$ where $x$ is numeric.
Since the problem is ambiguous, we move to the next.
3. **Problem statement:** Given $\angle A = 70^\circ$ and $\angle 2x$ is an acute angle, find $x$.
Since $2x$ is an acute angle, $0 < 2x < 90^\circ$.
If $\angle A = 70^\circ = 2x$, then
$$2x = 70^\circ \implies x = 35^\circ,$$
which is not among options. So likely $\angle A = 70^\circ$ and $\angle 2x$ is related differently.
Since the problem is unclear, move to next.
4. **Problem statement:** Find the area of a square with vertices at $(1,1)$ and $(4,4)$.
- The side length is the distance between these points along the square's side.
Distance between $(1,1)$ and $(4,4)$:
$$d = \sqrt{(4-1)^2 + (4-1)^2} = \sqrt{3^2 + 3^2} = \sqrt{18} = 3\sqrt{2}.$$
If these points are opposite corners of the square, the side length $s$ satisfies:
$$\text{diagonal} = s\sqrt{2} = 3\sqrt{2} \implies s = 3.$$
Area:
$$s^2 = 3^2 = 9.$$
Answer: 9.
5. **Problem statement:** The line $2y = 3x + 6$ intersects the positive $y$-axis. Find the length of the intercept.
- On the $y$-axis, $x=0$.
Substitute $x=0$:
$$2y = 6 \implies y = 3.$$
Length of intercept on positive $y$-axis is 3.
6. **Problem statement:** Find the radius of a circle with center at $(2,-3)$ passing through $(2,-1)$.
- Radius is distance between center and point:
$$r = \sqrt{(2-2)^2 + (-1 + 3)^2} = \sqrt{0 + 2^2} = 2.$$
Answer: 2.
**Final answers:**
4) Area = 9
5) Intercept length = 3
6) Radius = 2
Square Area 300532
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