Question

Instructions: Use the image and your knowledge of the

isosceles triangle to find the value of 2.

Answer 1

x = 36˚

Explanation:

• The 2 base angles in an isosceles triangle are equal
• Angles in a triangle sum to 180˚
• 
  `x+72+72=180`
• 
  `x+144=180`
• 
  `x=180-144=36`

Answer 2

Explanation:

In isosceles triangle, the base angles (the angles opposite to equal sides) are equal.

∠A = ∠B = 72

72+ 72 + x = 180 {Angle sum property of triangle}

144 + x = 180

x = 180 - 144

x = 36°