SOLUTION: A children's play area is trI angular. The sides of the play area measure 90m, 225m and 255m respectively. Calculate the area of the play area.

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Question 1037402: A children's play area is trI angular. The sides of the play area measure 90m, 225m and 255m respectively.
Calculate the area of the play area.
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39621) About Me  (Show Source):
You can put this solution on YOUR website!
Choose any side to serve as a base. A good choice is the 90 meter side, because this triangle is isosceles with two equal sides 225 meters. The triangle is composed of two congruent right triangles sharing a height; this height being the longer leg of either right triangle. Call this h.

45%5E2%2Bh%5E2=225%5E2
h%5E2=225%5E2-45%5E2
h%5E2=%28225%2B45%29%28225-45%29
h%5E2=270%2A180
h%5E2=3%2A3%2A3%2A2%2A5%2A2%2A3%2A3%2A2%2A5
h%5E2=2%5E3%2A3%5E5%2A5%5E2
h=2%2A3%2A5%2Asqrt%282%2A3%29
OR
highlight_green%28h=30%2Asqrt%286%29%29


Formula for area of a triangle: highlight_green%28%281%2F2%29bh%29, using b for base, and the same h for height.

Answer by ikleyn(52817) About Me  (Show Source):
You can put this solution on YOUR website!
.
A children's play area is trI angular. The sides of the play area measure 90m, 225m and 255m respectively.
Calculate the area of the play area.
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Use the Heron's formula.

See the lessons
    - Proof of the Heron's formula for the area of a triangle
    - One more proof of the Heron's formula for the area of a triangle
in this site.

The rest is arithmetic.

The previous solution is wrong.