Title: Math 7 Test Expressions
Course: quiz duplicate error

Q: Simplify the expression by combining like terms.

3y - y - 10y
- -7y - y (This is not completely simplified. You could still subtract the y from -7y.)
- -7y (incorrect)
- -6y (incorrect)
- -8y (correct)
A: -8y
Partly right: -7y - y (50%)

Q: Simplify the expression by combining like terms.

3x + 4 - 5x + 2
- 8x + 6 (Incorrect. The 5x was subtracted.)
- -2x + 6 (correct)
- 4x (incorrect)
- 4 (incorrect)
A: -2x + 6
Partly right: 8x + 6 (25%)

Q: Multiply.

4(y - 4)
- 4y - 16 (correct)
- 4y - 8 (4*4 = 16, not 8.)
- y - 16 (incorrect)
- 4y - 4 (incorrect)
A: 4y - 16
Partly right: 4y - 8 (25%)

Q: Multiply.

-7(2a + 3)
- -35a (Incorrect. Don't add a's and ones together.)
- -14a - 21 (correct)
- -14a + 3 (Incorrect. You need to multiply the -7 to the 3 as well.)
- -14a + 21 (Incorrect. It was a -7 you were multiplying by, so the 21 should be negative.)
A: -14a - 21
Partly right: -14a + 21 (25%)

Q: Use the distributive property to simplify the expression.

-(-6m + 5n - 3)
- -6m + 5n + 3 (incorrect)
- 6m - 5n - 3 (incorrect)
- -mn - 3 (incorrect)
- 6m - 5n + 3 (correct)
A: 6m - 5n + 3

Q: Simplify the expression.

6(x + 3) - 9 + 4x
- 10x + 9 (correct)
- -2x + 9 (incorrect)
- 10x - 27 (incorrect)
- 10x + 27 (incorrect)
A: 10x + 9

Q: Simplify the expression.

9x - 3(6 - x) + 35
- 12x + 17 (correct)
- 8x + 17 (incorrect)
- 12x + 53 (incorrect)
- 6x + 53 (incorrect)
A: 12x + 17

Q: Factor the expression:

15x - 25
- 5(3x - 5)
- 15(x - 25)
- 25(15x - 1)
- 3(5x - 8)
A: 5(3x - 5)

Q: Factor the expression: 8x + 80
A: 8(x + 10) / 8(x+10) / 8(x +10) / 8(x+ 10) / 8(1x+10) / 8(1x + 10)
Partly right: 4(2x + 20) (50%); 2(4x + 40) (50%); 4(2x+20) (50%); 4(2x+20) (50%)
Feedback ("4(2x + 20)"): You could factor out an 8.
Feedback ("2(4x + 40)"): You could factor out an 8.

Q: Write the phrase as an algebraic expression. Let x represent the unknown number.

Three times a number, decreased by 49
- 49 - 3x (incorrect)
- 3x - 49 (correct)
- 3x + 49 (incorrect)
- x - 49 (incorrect)
A: 3x - 49

Q: Christina earned $420. She spent some of her earnings on her phone bill and spent $100 on new clothes. Represent the amount of money Christina now has.
- 420 – (p + 100)
- 420 + (p + 100)
- 420 + 100p
- 420 + 100 – p
A: 420 – (p + 100)

Q: Evaluate.

10z- 4, for z = 6
- 65
- 55
- 56
- 64
A: 56

Q: Evaluate a - b  for a = -6 and b = -2
A: -4
Partly right: -8 (25%)
Feedback ("-8"): You needed to subtract b from a, not add them together.

Q: Simplify.

2t + 6(3 – 5t)
- -28t + 18 (correct)
- 20t + 18 (incorrect)
- -28t + 9 (incorrect)
- 20t + 9 (incorrect)
A: -28t + 18

Q: Simplify the expression by combining like terms.

9b - 2b + 7
- 14b (incorrect)
- 7b + 7 (correct)
- -7b + 7 (incorrect)
- 11b + 7 (Incorrect. The 2b was subtracted.)
A: 7b + 7
Partly right: 11b + 7 (25%)

Q: Rewrite the expression using the distributive property:

3(4x - 5)
- 3(4x) - 3(5)
- 3(4x) - 5 (You need to multiply the 3 to both the 4x and the 5)
- 4x - 3(5) (You need to multiply the 3 to both the 4x and the 5)
- 3(-1x)
A: 3(4x) - 3(5)
Partly right: 3(4x) - 5 (25%); 4x - 3(5) (25%)

Q: I understand that this is a test and that I must do it on my own without help from anyone else or notes.
- True
- False
A: True