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Lesson Example Discussion Quiz: Class Homework

Step-1

Title: Parallel Lines

Grade: 6-a Lesson: S2-L7

Explanation: Hello Students, time to practice and review the steps for the problem.

Lesson Steps

Step	Type	Explanation	Answer
1	Problem	If AB is parallel to CD, find the value of x in the following figure if the value of y = 107°.
2	Step	There are two angles marked in the figure: y is given as	107°
3	Step	Look at the figure where line AB is drawn parallel to line CD.
4	Step	We have an equation for the angle x:	5x + 12
5	Hint	Because AB is parallel to CD, certain angles have special relationships.
6	Step	The angle formed by equation 5x + 12 = y,we can set up the equation:	5x + 12 = 107
7	Step	Subtract 12 from both sides of the equation to simplify it	⇒ 5x + 12 - 12 = 107 - 12 ⇒ 5x = 95
8	Step	Divide each side of the equation by 5 to find the value of	⇒ \$(5x)/5 = 95/5\$ ⇒ x = 19
9	Step	The value of x is 19°.
10	SumUp	Can you summarize what you’ve understood in the above steps?
11	Choice.A	This is not correct because it does not match the correctly calculated value for angle x, which is 19°	20°
12	Choice.B	This is not correct because it does not match the correctly calculated value for angle x, which is 19°	91°
13	Choice.C	This is not correct because angle x is given as 107°, and if AB is parallel to CD, angle x and angle y would be equal, not 90°	90°
14	Choice.D	This is correct because it match the correctly calculated value for angle x, which is 19°	19°
15	Answer	Option	D
16	SumUp	Can you summarize what you’ve understood in the above steps?

Step

Type

Explanation

Answer

Problem

If AB is parallel to CD, find the value of x in the following figure if the value of y = 107°.

Step

There are two angles marked in the figure: y is given as

107°

Step

Look at the figure where line AB is drawn parallel to line CD.

Step

We have an equation for the angle x:

5x + 12

Hint

Because AB is parallel to CD, certain angles have special relationships.

Step

The angle formed by equation 5x + 12 = y,we can set up the equation:

5x + 12 = 107

Step

Subtract 12 from both sides of the equation to simplify it

⇒ 5x + 12 - 12 = 107 - 12
⇒ 5x = 95

Step

Divide each side of the equation by 5 to find the value of

⇒ \$(5x)/5 = 95/5\$
⇒ x = 19

Step

The value of x is 19°.

SumUp

Can you summarize what you’ve understood in the above steps?

Choice.A

This is not correct because it does not match the correctly calculated value for angle x, which is 19°

20°

Choice.B

This is not correct because it does not match the correctly calculated value for angle x, which is 19°

91°

Choice.C

This is not correct because angle x is given as 107°, and if AB is parallel to CD, angle x and angle y would be equal, not 90°

90°

Choice.D

This is correct because it match the correctly calculated value for angle x, which is 19°

19°

Answer

Option

SumUp

Can you summarize what you’ve understood in the above steps?