ASVAB Math Knowledge Practice Test 989322 Results

Your Results Global Average
Questions 5 5
Correct 0 2.65
Score 0% 53%

Review

1

Simplify (4a)(2ab) - (2a2)(8b).

62% Answer Correctly
24ab2
60a2b
8ab2
-8a2b

Solution

To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.

(4a)(2ab) - (2a2)(8b)
(4 x 2)(a x a x b) - (2 x 8)(a2 x b)
(8)(a1+1 x b) - (16)(a2b)
8a2b - 16a2b
-8a2b


2

Solve for y:
y2 + 3y - 27 = 5y - 3

48% Answer Correctly
9 or 7
1 or -7
-4 or 6
8 or -9

Solution

The first step to solve a quadratic expression that's not set to zero is to solve the equation so that it is set to zero:

y2 + 3y - 27 = 5y - 3
y2 + 3y - 27 + 3 = 5y
y2 + 3y - 5y - 24 = 0
y2 - 2y - 24 = 0

Next, factor the quadratic equation:

y2 - 2y - 24 = 0
(y + 4)(y - 6) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (y + 4) or (y - 6) must equal zero:

If (y + 4) = 0, y must equal -4
If (y - 6) = 0, y must equal 6

So the solution is that y = -4 or 6


3

The dimensions of this trapezoid are a = 5, b = 2, c = 8, d = 5, and h = 3. What is the area?

51% Answer Correctly
7\(\frac{1}{2}\)
10\(\frac{1}{2}\)
37\(\frac{1}{2}\)
40

Solution

The area of a trapezoid is one-half the sum of the lengths of the parallel sides multiplied by the height:

a = ½(b + d)(h)
a = ½(2 + 5)(3)
a = ½(7)(3)
a = ½(21) = \( \frac{21}{2} \)
a = 10\(\frac{1}{2}\)


4

Which of the following is not true about both rectangles and squares?

63% Answer Correctly

the perimeter is the sum of the lengths of all four sides

the lengths of all sides are equal

all interior angles are right angles

the area is length x width


Solution

A rectangle is a parallelogram containing four right angles. Opposite sides (a = c, b = d) are equal and the perimeter is the sum of the lengths of all sides (a + b + c + d) or, comonly, 2 x length x width. The area of a rectangle is length x width. A square is a rectangle with four equal length sides. The perimeter of a square is 4 x length of one side (4s) and the area is the length of one side squared (s2).


5

The endpoints of this line segment are at (-2, 10) and (2, -2). What is the slope-intercept equation for this line?

41% Answer Correctly
y = x - 3
y = -3x + 4
y = 1\(\frac{1}{2}\)x + 2
y = 2x + 1

Solution

The slope-intercept equation for a line is y = mx + b where m is the slope and b is the y-intercept of the line. From the graph, you can see that the y-intercept (the y-value from the point where the line crosses the y-axis) is 4. The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, 10) and (2, -2) so the slope becomes:

m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-2.0) - (10.0)}{(2) - (-2)} \) = \( \frac{-12}{4} \)
m = -3

Plugging these values into the slope-intercept equation:

y = -3x + 4