1. **Problem Statement:**
Points A and B are 60 m apart on level ground with a vertical tower between them.
From A, the angle of elevation to the tower top is 30°.
From B, the angle of elevation is 45°.
Find:
a) Horizontal distance from A to the tower base.
b) Height of the tower.
2. **Setup and notation:**
Let $x$ be the horizontal distance from A to the tower base.
Then the distance from B to the tower base is $60 - x$.
Let $h$ be the height of the tower.
3. **Using tangent of angles:**
From A: $\tan 30^\circ = \frac{h}{x}$
From B: $\tan 45^\circ = \frac{h}{60 - x}$
Recall:
$\tan 30^\circ = \frac{1}{\sqrt{3}}$
$\tan 45^\circ = 1$
4. **Write equations:**
From A:
$$h = x \times \frac{1}{\sqrt{3}} = \frac{x}{\sqrt{3}}$$
From B:
$$h = 1 \times (60 - x) = 60 - x$$
5. **Equate the two expressions for $h$:**
$$\frac{x}{\sqrt{3}} = 60 - x$$
6. **Solve for $x$:**
Multiply both sides by $\sqrt{3}$:
$$x = (60 - x) \sqrt{3}$$
$$x = 60\sqrt{3} - x\sqrt{3}$$
Bring terms with $x$ to one side:
$$x + x\sqrt{3} = 60\sqrt{3}$$
Factor $x$:
$$x(1 + \sqrt{3}) = 60\sqrt{3}$$
$$x = \frac{60\sqrt{3}}{1 + \sqrt{3}}$$
7. **Rationalize denominator:**
$$x = \frac{60\sqrt{3}}{1 + \sqrt{3}} \times \frac{1 - \sqrt{3}}{1 - \sqrt{3}} = \frac{60\sqrt{3}(1 - \sqrt{3})}{1 - 3} = \frac{60\sqrt{3} - 60 \times 3}{-2} = \frac{60\sqrt{3} - 180}{-2}$$
Divide numerator and denominator:
$$x = \frac{60\sqrt{3} - 180}{-2} = -30\sqrt{3} + 90 = 90 - 30\sqrt{3}$$
8. **Calculate numerical value:**
$\sqrt{3} \approx 1.732$
$$x \approx 90 - 30 \times 1.732 = 90 - 51.96 = 38.04 \text{ m}$$
9. **Find height $h$:**
Using $h = \frac{x}{\sqrt{3}}$:
$$h = \frac{38.04}{1.732} \approx 21.95 \text{ m}$$
**Final answers:**
a) Horizontal distance from A to tower base is approximately $38.04$ m.
b) Height of the tower is approximately $21.95$ m.
Tower Distance Height A446D6
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