Answer:
An equilateral triangle has three lines of symmetr
Step-by-step explanation:
letter d
Answer:
o/3 or 1/1
Step-by-step explanation:
For number 4, we'll need a few facts to answer our question:
- Two supplementary angles add up to 180°, forming a straight angle (the angle formed by a straight line)
- The interior angles of a triangle add up to 180°
Given those, we notice that the one unlabeled angle in the figure shares a line with 156°. In fact, this angle is <em>supplementary</em> to 156°, which means that the two add up to 180°. To find the measure of this mystery angle, we can subtract 156 from 180 to obtain 180 - 156 = 24°.
Now, let's look at the triangle. We already know the measure of one of the angles is 24°, and the other two are x°. What else do we know about the angles of a triangle? From the two facts listed at the beginning, we know their interior angles add up to 180°, so let's use that fact to solve for x.
We have:

, or

Solving for x:

So, x = 78°.
For question 5, the <em>definition</em> of a pair of parallel lines is a pair of lines which <em>never intersect</em>, so "always" would be the appropriate answer.
Answer:
m∠A = 50°
m∠E = 50°
Step-by-step explanation:
7x - 17 and 2x + 8 are same side exterior angles. They have a sum of 180°.
7x - 17 + 2x + 8 = 180
9x - 9 = 180
9x = 189
x = 21
∠A and 7x - 17 are supplementary. ∠E and 2x + 8 are vertical angles.
m∠A + 7x - 17 = 180
m∠A + 7(21) - 17 = 180
m∠A + 147 - 17 = 180
m∠A + 130 = 180
m∠A = 50
m∠E = 2x + 8
m∠E = 2(21) + 8
m∠E = 42 + 8
m∠E = 50