Triangle Area Calculation: Given Perimeter 24 and Height 5

Question

Calculate the area of the triangle ABC:

Given that: Perimeter=24

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Video Solution

Solution Steps

00:00 Calculate the area of triangle ABC
00:02 The perimeter of the triangle equals the sum of its sides
00:10 Substitute in the relevant values and proceed to calculate to determine BC
00:22 Isolate BC
00:31 Now we have the length of base BC
00:37 Apply the formula for calculating the triangle's area
00:41 (base(BC) x height(AE)) divided by 2
00:50 Substitute in the relevant values and proceed to solve
01:02 This is the solution

Step-by-Step Solution

To find the area of triangle ABC \triangle ABC , follow these steps:

  • Step 1: Since the perimeter is 24, and using the side lengths AB=8 AB = 8 , AC=7 AC = 7 , we calculate the third side BC BC . Using AB+AC+BC=24 AB + AC + BC = 24 , we find:
  • 8+7+BC=24    BC=2415=9 8 + 7 + BC = 24 \implies BC = 24 - 15 = 9
  • Step 2: Given that the height from point A A to base BC BC is 5, use the triangle area formula:
  • Area=12×base×height \text{Area} = \frac{1}{2} \times \text{base} \times \text{height}

    Substituting base BC=9 BC = 9 and height = 5:

    Area=12×9×5=452=22.5 \text{Area} = \frac{1}{2} \times 9 \times 5 = \frac{45}{2} = 22.5

Therefore, the area of triangle ABC \triangle ABC is 22.5 22.5 .

Answer

22.5