| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.85 |
| Score | 0% | 57% |
The dimensions of this cube are height (h) = 8, length (l) = 3, and width (w) = 3. What is the surface area?
| 306 | |
| 138 | |
| 114 | |
| 236 |
The surface area of a cube is (2 x length x width) + (2 x width x height) + (2 x length x height):
sa = 2lw + 2wh + 2lh
sa = (2 x 3 x 3) + (2 x 3 x 8) + (2 x 3 x 8)
sa = (18) + (48) + (48)
sa = 114
Which of the following is not required to define the slope-intercept equation for a line?
y-intercept |
|
x-intercept |
|
slope |
|
\({\Delta y \over \Delta x}\) |
A line on the coordinate grid can be defined by a slope-intercept equation: y = mx + b. For a given value of x, the value of y can be determined given the slope (m) and y-intercept (b) of the line. The slope of a line is change in y over change in x, \({\Delta y \over \Delta x}\), and the y-intercept is the y-coordinate where the line crosses the vertical y-axis.
If a = c = 8, b = d = 9, what is the area of this rectangle?
| 28 | |
| 20 | |
| 49 | |
| 72 |
The area of a rectangle is equal to its length x width:
a = l x w
a = a x b
a = 8 x 9
a = 72
What is the circumference of a circle with a diameter of 7?
| 36π | |
| 7π | |
| 20π | |
| 28π |
The formula for circumference is circle diameter x π:
c = πd
c = 7π
Find the value of a:
-7a + z = 3
-2a + 2z = -3
| -1\(\frac{5}{27}\) | |
| 2\(\frac{1}{2}\) | |
| 1\(\frac{4}{7}\) | |
| -\(\frac{3}{4}\) |
You need to find the value of a so solve the first equation in terms of z:
-7a + z = 3
z = 3 + 7a
then substitute the result (3 - -7a) into the second equation:
-2a + 2(3 + 7a) = -3
-2a + (2 x 3) + (2 x 7a) = -3
-2a + 6 + 14a = -3
-2a + 14a = -3 - 6
12a = -9
a = \( \frac{-9}{12} \)
a = -\(\frac{3}{4}\)