I dont like math. Help

I can't help you with that. I'm sorry. I get that math is a hard thing to like, but can you at least try?

So in the first video can another way of solving it be; 180-121=59 instead of going through the whole process. I just want to know if it's going to work for other problems like it.

If the problem stated that the two diagonal lines were parallel, then you'd be able to assume angle x was equal to the angle Sal solved for at timestamp 1:08 in the video. Then you'd jest be able to do _180 - 121 = 59 = x_. Since the problem didn't state that the lines were parallel, you wouldn't be able to assume that. For this problem, the lines ended up being parallel, so that logic did work out. Though lines that look close to parallel may not actually be parallel in all problems, so it's safer to do all the math. However, you could first try and prove the lines were parallel, and then you'd be able to follow that logic. If you were pressed for time on the real SAT when you got that problem, you could just use your gut instinct and do _180 - 121 = 59 = x_. Though if you have the time, it's good to do the math out. Have a great day! (:

Main content

SAT (Fall 2023)

Course: SAT (Fall 2023) > Unit 6

Lesson 6: Additional Topics in Math: lessons by skill

Congruence and similarity | Lesson

Google Classroom

What are congruence and similarity problems, and how frequently do they appear on the test?

Congruence and similarity problems ask us to use

and

(shown below) to solve problems.

On your official SAT, you'll likely see 1 to 2 questions about congruence and similarity.

You can learn anything. Let's do this!

What are some common ways the SAT combines angle relationships?

Finding angles in triangles

Khan Academy video wrapper

Worked example: Triangle angles (intersecting lines)See video transcript

Triangles and other angle relationships

On the SAT, we're expected to find unknown angle measures when only a few are given. More often than not, triangles are involved.

At the beginning of each SAT math section, the following information is provided as reference:

The sum of the measures in degrees of the angles of a triangle is $180$ ‍.

Triangles, vertical angles, and supplementary angles

One common type of figure on the SAT is a triangle formed by three intersecting lines, as shown below.

We know that

x^{\circ} + y^{\circ} + z^{\circ} = 180^{\circ}

, but we also know how the angles outside the triangle relate to the inside angles based on the properties of

and

Triangles and parallel lines

Another common type of figure shows

constructed using parallel lines.

Two similar triangles can be constructed from two parallel lines and two intersecting transversals, as shown below.

Note: Since the two triangles have different orientations, be careful when identifying the corresponding sides! In two similar triangles, the longest side in one corresponds to the longest side in the other and so on.

Two similar triangles can also be constructed by drawing a line inside a triangle that's parallel to one of the sides. In the example shown below, the line inside the triangle is parallel to the base of the triangle and divides the larger triangle into a similar smaller triangle and a quadrilateral.

Try it!

try: find angle measures in an intersection of three lines

Based on the figure above, what is the value of

a

What is the value of

b

What is the value of

c

try: find angle measures of parallel lines and transversals

The figure above shows two horizontal lines and two intersecting transversals.

What is the value of

a

What is the value of

b

What is the value of

c

How do I use similarity to find side lengths?

Solving similar triangles

Khan Academy video wrapper

Solving similar trianglesSee video transcript

Setting up proportional relationships using similarity

Similar triangles have the same shape, but aren't necessarily the same size. In the figure below, triangles

A B C

and

X Y Z

are similar: they have the same angle measures, but not the same side lengths.

The corresponding side lengths of similar triangles are related by a constant ratio, which we can call

k

. For similar triangles

A B C

and

X Y Z

, the following is true:

\begin{aligned} X Y & = k (A B) \\ Y Z & = k (B C) \\ X Z & = k (A C) \\ \frac{X Y}{A B} & = \frac{Y Z}{B C} = \frac{X Z}{A C} = k \end{aligned}

Let's try applying the properties of similar triangles. In the figure below,

\overset{―}{B D}

is parallel to

\overset{―}{A E}

. If

B C = 10

B D = 14

, and

A E = 21

, what is the length of

\overset{―}{A C}

[Show me!]

Try it!

try: use similarity to find side length

In the figure above, triangles

A B D

and

B C D

are similar. The length of

\overset{―}{B D}

6

, and the length of

\overset{―}{C D}

12

Based on the figure,

\overset{―}{C D}

is the

of triangle

B C D

, and

\overset{―}{B D}

is both the

of triangle

B C D

and the

of triangle

A B D

What is the length of

\overset{―}{A D}

Your turn!

practice: find an angle measure

Intersecting lines

p

q

, and

r

are shown above. What is the value of

x

practice: find an angle measure

In the figure above, lines

ℓ

and

m

are parallel,

y = 30

, and

z = 45

. What is the value of

x

practice: find a side length

In the figure above, segments

A B

and

D E

are parallel, and segments

A D

and

B E

intersect at

C

. What is the length of segment

B E

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Noah T
Posted a year ago. Direct link to Noah T's post “I dont like math. Help”
I dont like math. Help
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- PizzaMan21
  Posted 6 months ago. Direct link to PizzaMan21's post “I can't help you with tha...”
  I can't help you with that. I'm sorry.
  
  I get that math is a hard thing to like, but can you at least try?
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  (3 votes)
dagmaweamanuel
Posted 5 months ago. Direct link to dagmaweamanuel's post “This in my opinion, is th...”
This in my opinion, is the worst topic to go through compared to the rest.
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redemptionottah06
Posted 2 years ago. Direct link to redemptionottah06's post “So in the first video can...”
So in the first video can another way of solving it be;
180-121=59 instead of going through the whole process. I just want to know if it's going to work for other problems like it.
Button navigates to signup pageButton navigates to signup page
(0 votes)
Answer
- Evan
  Posted 2 years ago. Direct link to Evan's post “If the problem stated tha...”
  If the problem stated that the two diagonal lines were parallel, then you'd be able to assume angle x was equal to the angle Sal solved for at timestamp
  1:08
  in the video. Then you'd jest be able to do 180 - 121 = 59 = x. Since the problem didn't state that the lines were parallel, you wouldn't be able to assume that. For this problem, the lines ended up being parallel, so that logic did work out. Though lines that look close to parallel may not actually be parallel in all problems, so it's safer to do all the math. However, you could first try and prove the lines were parallel, and then you'd be able to follow that logic.
  
  If you were pressed for time on the real SAT when you got that problem, you could just use your gut instinct and do 180 - 121 = 59 = x. Though if you have the time, it's good to do the math out.
  
  Have a great day! (:
  Button navigates to signup page
  (6 votes)
staRRaRRR
Posted a month ago. Direct link to staRRaRRR's post “for those who need more r...”
for those who need more review on congruence and similarity clarifications, try reading this article:
https://www.khanacademy.org/test-prep/praxis-math/praxis-math-lessons/gtp--praxis-math--lessons--geometry/a/gtp--praxis-math--article--congruence-and-similarity--lesson

hope it helps n hope everyone gets their ideal score!!
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(1 vote)
Answer