Keystone Test Algebra: Linear Equations/Inequalities 3

Question 1

Which of the following is equivalent to 5 − 2(x + 3) = 7?

Accepted Answer

5 − 2x − 6 = 7

Answer

Distributing −2 over (x + 3) gives −2x − 6, so the equation becomes 5 − 2x − 6 = 7.

Question 2

What is the x-intercept of the line y = 2x − 10?

Accepted Answer

(5, 0)

Answer

Set y = 0 and solve: 0 = 2x − 10 gives 2x = 10, so x = 5; the x-intercept is (5, 0).

Question 3

Solve: (x/3) + 4 = 7

Accepted Answer

x = 9

Answer

Subtract 4 from both sides: x/3 = 3; multiply both sides by 3: x = 9.

Question 4

A number is doubled and then decreased by 11. The result is 13. What is the number?

Accepted Answer

12

Answer

Translate to 2n − 11 = 13; add 11: 2n = 24; divide by 2: n = 12.

Question 5

Which inequality has x = −2 as a solution?

Accepted Answer

2x − 1 ≥ −5

Answer

Substituting x = −2 into 2x − 1 ≥ −5 gives 2(−2) − 1 = −5 ≥ −5, which is true.

Keystone Test Practice Test