Deltoid Geometry: Finding AC Length Given Area 60 cm² and BD = 12 cm

Question

Given the deltoid ABCD

Side length BD equals 12 cm

The area of the deltoid is equal to 60 cm².

Find the length of the side AC

S=60S=60S=60121212AAABBBCCCDDD

Video Solution

Solution Steps

00:00 Find AC
00:03 We'll use the formula for calculating the area of a kite
00:07 (diagonal times diagonal) divided by 2
00:12 We'll substitute appropriate values according to the given data and solve for AC
00:21 Divide 12 by 2
00:25 Isolate AC
00:34 And this is the solution to the question

Step-by-Step Solution

To find the length of side AC AC in the given deltoid:

  • Step 1: Write down the area formula for a kite: S=12×BD×AC S = \frac{1}{2} \times BD \times AC , where S S is the area, and BD BD and AC AC are the diagonals.
  • Step 2: Plug in the known values: 60=12×12×AC 60 = \frac{1}{2} \times 12 \times AC .
  • Step 3: Simplify the equation: 60=6×AC 60 = 6 \times AC .
  • Step 4: Solve for AC AC :

AC=606=10 AC = \frac{60}{6} = 10 cm.

Therefore, the length of side AC AC is 10 10 cm.

Answer

10 10 cm