Lines
ab
and
ac
tangent to circle k(o) at b and c respectively. find bc, if m∠oab=30°, and ab=5 cm.

5 cm

Step-by-step explanation:

If AB is tangent to the circle k(O), then radius OB is perpendicular to segment AB.

If BC is tangent to the circle k(O), then radius OC is perpendicular to segment AC.

Consider two right triangles ABO and ACO. In these triangles:

By HL theorem, triangles ABO and ACO are congruent. Then

Hence, ∠BAC=∠OAB+∠OAC=30°+30°=60°.

Consider triangle ABC, this triangle is isosceles triangle. In isosceles triangles angles adjacent to the base are congruent, thus

∠CBA=∠BCA=1/2(180°-60°)=60°.

Therefore, triangle ABC is an equilateral triangle, so BC=AB=AC=5 cm.

yes

step-by-step explanation:

part d

step-by-step explanation:

theresa talked her parents into getting sd cards for her phone and her brother’s phone. inserting an sd card into a phone gives it more storage. they both get 8-gigabyte sd cards. how many bits of storage come with each sd card? type your answer in both scientific and standard notation.