Answer:
70
Step-by-step explanation:
all angles in a triangle add up to 180
if two sides are equal their angles are equal
180-40
140÷2
70
Step-by-step explanation:
a. true
property: identity
b. false
property: communitive
c. true
associative
d. false
property: multiplication property of zero
Answer:
If AB is a tangent to the circle, the triangle ABO is right angled, as the angle where a tangent meets the circumference is always 90 degrees.
We also know that Pythogoras' theorem only holds for right angled triangles.
The hypotenuse is 12 + 8 as 12 is the radius so is 20.
16^2+12^2 = 256 + 144 = 400 = 20^2 so AB must be tangent.
