| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.32 |
| Score | 0% | 66% |
What is 5a9 + 8a9?
| 40a9 | |
| 13a9 | |
| 40a18 | |
| a918 |
To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.
5a9 + 8a9 = 13a9
If side a = 3, side b = 2, what is the length of the hypotenuse of this right triangle?
| \( \sqrt{13} \) | |
| \( \sqrt{61} \) | |
| \( \sqrt{145} \) | |
| \( \sqrt{106} \) |
According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:
c2 = a2 + b2
c2 = 32 + 22
c2 = 9 + 4
c2 = 13
c = \( \sqrt{13} \)
The formula for volume of a cube in terms of height (h), length (l), and width (w) is which of the following?
h x l x w |
|
lw x wh + lh |
|
h2 x l2 x w2 |
|
2lw x 2wh + 2lh |
A cube is a rectangular solid box with a height (h), length (l), and width (w). The volume is h x l x w and the surface area is 2lw x 2wh + 2lh.
The dimensions of this cube are height (h) = 8, length (l) = 2, and width (w) = 3. What is the surface area?
| 146 | |
| 92 | |
| 104 | |
| 34 |
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 2 x 3) + (2 x 3 x 8) + (2 x 2 x 8)
sa = (12) + (48) + (32)
sa = 92
The formula for the area of a circle is which of the following?
a = π d2 |
|
a = π r2 |
|
a = π r |
|
a = π d |
The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)2 : a = π r2.