Let's solve each part of the problem step by step.
---
Part 1: Find x in the first diagram
We have a straight line with an angle of
34° and another angle labeled
x, forming a linear pair (they are adjacent angles on a straight line).
>
Linear Pair Theorem: The sum of angles on a straight line is
180°.
So:
$$
x + 34^\circ = 180^\circ
$$
$$
x = 180^\circ - 34^\circ = 146^\circ
$$
✔ Answer: $ x = 146^\circ $
---
Part e: Triangle ABC, find ∠ACB
We are given:
- $ \angle B = 30^\circ $
- Exterior angle at C is $ 120^\circ $
- We need to find $ \angle ACB $, which is the interior angle at C.
#### Step 1: Use exterior angle property
>
Exterior Angle Theorem: The exterior angle of a triangle is equal to the sum of the two opposite interior angles.
But here, we can use the fact that:
$$
\text{Interior angle at } C + \text{Exterior angle at } C = 180^\circ
$$
$$
\angle ACB + 120^\circ = 180^\circ
$$
$$
\angle ACB = 180^\circ - 120^\circ = 60^\circ
$$
✔ So, $ \angle ACB = 60^\circ $
Now, let’s verify using triangle angle sum:
We already know:
- $ \angle B = 30^\circ $
- $ \angle C = 60^\circ $
- Sum of angles in a triangle = $ 180^\circ $
So:
$$
\angle A = 180^\circ - 30^\circ - 60^\circ = 90^\circ
$$
So $ x = \angle A = 90^\circ $
But the question only asks for $ \angle ACB $, so:
✔ Answer: $ \angle ACB = 60^\circ $
---
Part f: Regular quadrilateral — find exterior angles w, x, z, y
A
regular quadrilateral means all sides and angles are equal. That is a
square.
In a square:
- Each interior angle = $ 90^\circ $
- Each exterior angle = $ 180^\circ - 90^\circ = 90^\circ $
Because:
- Exterior angle = $ 180^\circ - \text{interior angle} $
- And since it's regular, all exterior angles are equal.
So:
- $ w = 90^\circ $
- $ x = 90^\circ $
- $ y = 90^\circ $
- $ z = 90^\circ $
> Note: The labels w, x, z, y likely refer to the four exterior angles at the vertices (in order), but since it's regular, they're all the same.
✔ Answers:
- $ w = 90^\circ $
- $ x = 90^\circ $
- $ y = 90^\circ $
- $ z = 90^\circ $
---
✔ Final Answers:
First diagram:
- $ x = 146^\circ $
e. $ \angle ACB = 60^\circ $
f. Regular quadrilateral:
- $ w = 90^\circ $
- $ x = 90^\circ $
- $ y = 90^\circ $
- $ z = 90^\circ $
Let me know if you'd like this formatted for a worksheet!
Parent Tip: Review the logic above to help your child master the concept of 6th grade math worksheet angles.