NCDAP Elementary Algebra 4

Question 1

Solve for x: x/3 + 4 = 9

Accepted Answer

15

Answer

Subtracting 4 gives x/3 = 5, then multiplying by 3 gives x = 15.

Question 2

Which expression represents 'twice the sum of a number and 6'?

Accepted Answer

2(n + 6)

Answer

'Twice the sum' means you multiply the entire sum (n + 6) by 2, giving 2(n + 6).

Question 3

If f(x) = x² - 2x + 1, what is f(3)?

Accepted Answer

4

Answer

f(3) = 3² - 2(3) + 1 = 9 - 6 + 1 = 4.

Question 4

What is the product of (x + 5)(x - 2)?

Accepted Answer

x² + 3x - 10

Answer

Using FOIL: x² - 2x + 5x - 10 = x² + 3x - 10.

Question 5

A rectangle has a perimeter of 36 feet. If the width is w, which equation shows the length l?

Accepted Answer

l = 18 - w

Answer

Perimeter = 2l + 2w = 36, so l + w = 18, giving l = 18 - w.

(NCDAP) North Carolina Diagnostic Placement Test Practice Test