7 checkpoint 3; 7.af.1

Enter the value of n so that the expression (−y + 5) + (7y − 9) is equivalent to (ny − 4).

n=?

Enter the value of n so that the expression −y + 5.3 + 7.2y − 9 is equivalent to 6.2y + n.

• n = -3.7

• n = 14.3

• n = 3.7

• n = -14.3

Which property is demonstrated by the expression shown? 2x + 6 − 3x + 2 = 2x − 3x + 6 + 2

• Distributive property

• Commutative property

• Associative property

• Inverse property

Which expression is equivalent to 36x + 9?

• 4x + 1

• 36(x + 1)

• 4(9x + 1)

• 9(4x + 1)

Select TWO expressions that are equivalent to −72x + 60.

• 8(−9x + 7)

• −12(−6x − 5)

• 6(−12x + 10)

• -8(9x - 7)

• −12(6x − 5)

Which expression is equivalent to -0.8(10.8x - 20 + 3.2x)?

• -11.2x + 16

• -11.2x - 16

• -8.64x - 16.8

• -8.64x + 16.8

A student wrote an equivalent expression to 1.2(2.2 + 3y - 3.7). The students’ steps are shown. Step 1: 1.2(2.2 + 3y - 3.7) Step 2: 2.64 + 3.6y - 4.44 Step 3: 2.64 - 4.44 + 3.6y Step 4: 7.08 + 3.6y Which statement identifies and explains the mistake the student made?

• The first mistake was in Step 3. The 3.6y should be negative and the 4.44 should be positive.

• The first mistake was in Step 3. When recording the terms, 2.64 should be the coefficient of y rather than 3.6.

• The first mistake was in Step 4. The 3.6 y should be negative.

• The first mistake was in Step 4. The student added 4.44 to 2.64 instead of subtracting 4.44 from 2.64.

Use the distributive property to simplify the expression. -4(3x - 7)

• -12x + 28

• -12x - 28

• 12x + 28

• 12x - 28

Simplify the expression. 5x + ½ (4x - 8)

• 5x + 2x - 4

• 7x - 4

• 7x - 8

• 5x + 2x - 8

A student claims that the expression -3(x - 2) is equivalent to -3x - 2. Which statement identifies and corrects the error in the student’s work?

• The student did not subtract 2 from -3x; the equivalent expression is -5x.

• The student did not subtract 2 from -3; the equivalent expression is -3x - 5.

• The student did not find the product of -3 and -2; the equivalent expression is -3x + 6.

• The student did not keep the parenthesis around -2; the equivalent expression is -3x(- 2).