Krishna
0

Step 1: Make a note of the known and unknown measurements

Step 2: Use formula of area of isosceles triangle to write

FORMULAS:

Area of an isosceles triangle = \frac{1}{2} b*h

Where b - base and h - height (altitude)

h (Altitude) = \sqrt{a^2 - \frac{b^2}{4}}

Step 3: Substitute the known values in the area formula.

EXAMPLE:  Area of an isosceles triangle = \frac{1}{2} b*h

20 = \frac{1}{2} 10 * h

Step 4: Simplify the equation and find the unknown value (Height)

EXAMPLE : h = \frac{20}{5}

h = 4

Step 5: Set up a formula to calculate the lateral side of an isosceles triangle.

NOTE: Isosceles triangle is a combination of two right triangle

Pythagoras theorem

FORMULA:(lateral\ side)^2=(height)^2+\left(\frac{base}{2}\right)^2

Step 6:  Find the lateral side of an isosceles triangle.

EXAMPLE: (lateral\ side)^2=4^2+(\frac{10}{2})^2

lateral\ side=\sqrt{16+25}

lateral\ side=\sqrt{41}