Step-by-step explanation:
3(p2q + pq2 - pq) - 6pq + 3pq2 =
3[-20 × 2 + (-20) × 2 - (-20)] - 6 × (-20) + 3 × 2 × (-20) =
3[-40 + (-40) + 20] - 6 × (-20) + 3 × 2 × (-20) =
3(-40 - 40 + 20) - 6 × (-20) + 3 × 2 × (-20) =
3(-80 + 20) - 6 × (-20) + 3 × 2 × (-20) =
3 × (-60) - 6 × (-20) + 3 × 2 × (-20) =
-180 + 120 + 6 × (-20) =
-180 + 120 + (-120) =
-180 + 120 - 120 =
-60 - 120 = -180
Answer: D: Corresponding parts of congruent triangles are congruent
Step-by-step explanation:
If two triangle are congruent using postulate of theorems of congruence then their corresponding parts are congruent by CPCTC rule.
The CPCTC rule says that if two triangles are congruent then their each corresponding part whether angles or sides must be equal.
Here if triangle abc= def by side-side-side triangle congruence theorem,
then b=e [which is a corresponding part of both triangles] by Corresponding parts of congruent triangles are congruent.
Answer:
9
Step-by-step explanation:
Sum of internal angles of any triangle = 180∘
∴x + 2x + 3x = 180∘
∴6x = 180∘
∴ x = 30∘
So the angles are: 30∘, 60∘ and 90∘
