Solve Equations Area Bearing
1. **Solve the equation** $(7p + 9) \tan 53^\circ = 143.8$.
2. Calculate $\tan 53^\circ$ using a calculator: $\tan 53^\circ \approx 1.3270$.
3. Substitute into the equation: $(7p + 9) \times 1.3270 = 143.8$.
4. Divide both sides by 1.3270: $7p + 9 = \frac{143.8}{1.3270} \approx 108.34$.
5. Subtract 9 from both sides: $7p = 108.34 - 9 = 99.34$.
6. Divide both sides by 7: $p = \frac{99.34}{7} \approx 14.2$.
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7. **Work out the area of the quadrilateral EFGH.**
8. The quadrilateral has right angles at E and H, with vertical sides EH = 8 cm and FG = 4 cm, and horizontal side HG = 11 cm.
9. The shape can be split into a rectangle and a right triangle by the diagonal EG.
10. The rectangle has dimensions 4 cm (FG) by 11 cm (HG), so area = $4 \times 11 = 44$ cm$^2$.
11. The triangle formed by EH and the difference in vertical sides is with height $8 - 4 = 4$ cm and base 11 cm.
12. Area of triangle = $\frac{1}{2} \times 11 \times 4 = 22$ cm$^2$.
13. Total area = rectangle area + triangle area = $44 + 22 = 66$ cm$^2$.
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14. **Find the bearing from C to D on the map.**
15. Coordinates: C at (2,4), D at (8,7) in grid units.
16. Calculate horizontal difference: $\Delta x = 8 - 2 = 6$.
17. Calculate vertical difference: $\Delta y = 7 - 4 = 3$.
18. Bearing is measured clockwise from North.
19. Calculate angle $\theta = \arctan\left(\frac{\Delta x}{\Delta y}\right) = \arctan\left(\frac{6}{3}\right) = \arctan(2) \approx 63.4^\circ$.
20. Bearing from C to D = $0^\circ + 63.4^\circ = 63^\circ$ (nearest degree).
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21. **Determine the best scale value A for the height axis graph.**
22. The height values range from 4 m to 58 m.
23. To choose a good scale, pick a value that divides the range into manageable intervals.
24. The range is $58 - 4 = 54$ m.
25. A suitable scale could be 10 m per interval, so $A = 10$.
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26. **Determine the best scale value A for the distance from home axis.**
27. Maximum distance from home is Joe's 62 km at 3 hours.
28. The axis should cover at least 62 km.
29. Choose a scale dividing 62 into equal intervals, e.g., 10 km per interval.
30. So, $A = 10$ is a good scale value.
**Final answers:**
- $p \approx 14.2$
- Area of quadrilateral = $66.0$ cm$^2$
- Bearing from C to D = $63^\circ$
- Best scale for height axis $A = 10$
- Best scale for distance from home axis $A = 10$