1. **State the problem:** We are given a right triangle PQR with a right angle at Q. Side PQ is vertical with length 8 cm, and the area of the triangle is 36 cm². We need to find the length of the hypotenuse PR.
2. **Formula for the area of a triangle:**
$$\text{Area} = \frac{1}{2} \times \text{base} \times \text{height}$$
3. **Identify base and height:**
Since angle Q is right, sides PQ and QR are perpendicular. We know PQ = 8 cm (height), and QR is the base (unknown length).
4. **Use the area to find QR:**
$$36 = \frac{1}{2} \times QR \times 8$$
Multiply both sides by 2:
$$72 = QR \times 8$$
Divide both sides by 8:
$$QR = \frac{72}{8}$$
Show cancellation:
$$QR = \frac{\cancel{72}}{\cancel{8}} = 9$$
So, QR = 9 cm.
5. **Find hypotenuse PR using Pythagoras theorem:**
$$PR^2 = PQ^2 + QR^2$$
$$PR^2 = 8^2 + 9^2 = 64 + 81 = 145$$
$$PR = \sqrt{145}$$
6. **Final answer:**
$$PR = \sqrt{145} \approx 12.04 \text{ cm}$$
Triangle Hypotenuse 94580E
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