Answer:
A. Since the 3 angles in ∆ABC are congruent to the corresponding 3 angles in ∆A'B'C', therefore, ∆ABC is similar to ∆A'B'C'.
B. A'B' = 30
Explanation:
A. Two triangles are said to be similar if their corresponding angles are congruent to each other.
To know whether ∆ABC and ∆A'B'C' are similar, let's find the measure of their angles each, and see if their corresponding angles are congruent to each other.
∆ABC:
m<A = 59°
m<B = 37°
m<C = 180 - (37 + 59) = 84°
∆A'B'C':
m<A' = 59°
m<B' = 180 - (59 + 84) = 37°
m<C' = 84°
As we can see,
Angle A is congruent to Angle A'
Angle B is congruent to Angle B'
Angle C is congruent to Angle C'
Therefore, since the 3 angles in ∆ABC are congruent to the corresponding 3 angles in ∆A'B'C', therefore, ∆ABC is similar to ∆A'B'C'.
B. AC = 8; A'C' = 12; AB = 20
Since ∆ABC is similar to ∆A'B'C', the ratio of their corresponding sides would be equal.
Therefore:
AC/A'C' = AB/A'B'
Plug in the values into the equation
8/12 = 20/A'B'
Cross multiply
A'B'*8 = 20*12
A'B'*8= 240
Divide both sides by 8
A'B' = 240/8
A'B' = 30