Preskoči na glavni sadržaj
Prijava
Sign up for FREE
arrow_back
Biblioteka

Open Up - Grade 7 - Mathematics - Unit 6 - Lesson 22

star
star
star
star
star
Posljednje ažuriranje over 4 years ago
13
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1
1
7.EE.1

"Source: Open Up Resouces (Download for free at openupresources.org.)"

Pitanje 1
1.

Jada says, “I can tell that \frac{-2}{3}(x + 5) + 4(x + 5) - \frac{10}{3}(x + 5) equals 0 just by looking at it.”

Is Jada correct?

Pitanje 2
2.

Are the following expressions equivalent?

A. 3x - 2x + 0.5x.

a. 1.5x

Pitanje 3
3.

Are the following expressions equivalent?

A. 3(x + 4) -2(x + 4).

a. x+3

Pitanje 4
4.

Are the following expressions equivalent?

A. 6(x + 4) -2(x + 5).

a. 2(2x + 7)

Pitanje 5
5.

Are the following expressions equivalent?

A. 3(x + 4) -2(x + 4)+0.5(x+4).

a. 1.5

Pitanje 6
6.

For each situation, write an expression for the new balance using as few terms as possible.

A checking account has a balance of -$126.89. A customer makes two deposits, one 3\frac{1}{2} times the other, and then withdraws $25.

Pitanje 7
7.

For each situation, write an expression for the new balance using as few terms as possible.

A checking account has a balance of $350. A customer makes two withdrawals, one $50 more than the other. Then he makes a deposit of $75.

Pitanje 8
8.

Tyler is using the distributive property on the expression 9 -4(5x - 6). Here is his work:

9-4(5x-6)

9+(-4)(5x+-6)

9+-20x+-6

3-20x

Mai thinks Tyler’s answer is incorrect. She says, “If expressions are equivalent then they are equal for any value of the variable. Why don’t you try to substitute the same value for x in all the equations and see where they are not equal?”

Find the step where Tyler made an error.

Pitanje 9
9.

Tyler is using the distributive property on the expression 9 -4(5x - 6). Here is his work:

9-4(5x-6)

9+(-4)(5x+-6)

9+-20x+-6

3-20x

Mai thinks Tyler’s answer is incorrect. She says, “If expressions are equivalent then they are equal for any value of the variable. Why don’t you try to substitute the same value for x in all the equations and see where they are not equal?”

Explain what he did wrong.

Pitanje 10
10.

Tyler is using the distributive property on the expression 9 -4(5x - 6). Here is his work:

9-4(5x-6)

9+(-4)(5x+-6)

9+-20x+-6

3-20x

Mai thinks Tyler’s answer is incorrect. She says, “If expressions are equivalent then they are equal for any value of the variable. Why don’t you try to substitute the same value for x in all the equations and see where they are not equal?”

Correct Tyler’s work.

Pitanje 11
11.

If (11+x) is positive, but (4+x) is negative, what is one number that x could be?

Pitanje 12
12.

if (-3+y) is positive, but (-9+y) is negative, what is one number that y could be

Pitanje 13
13.

if (-5+z) is positive, but (-6+z) is negative, what is one number that z could be