| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.54 |
| Score | 0% | 71% |
What is 8a9 - 3a9?
| 5a9 | |
| 11 | |
| 5a18 | |
| 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.
8a9 - 3a9 = 5a9
What is the circumference of a circle with a radius of 4?
| 28π | |
| 3π | |
| 12π | |
| 8π |
The formula for circumference is circle diameter x π. Circle diameter is 2 x radius:
c = πd
c = π(2 * r)
c = π(2 * 4)
c = 8π
If side x = 12cm, side y = 14cm, and side z = 10cm what is the perimeter of this triangle?
| 43cm | |
| 36cm | |
| 28cm | |
| 32cm |
The perimeter of a triangle is the sum of the lengths of its sides:
p = x + y + z
p = 12cm + 14cm + 10cm = 36cm
Which of the following statements about math operations is incorrect?
you can subtract monomials that have the same variable and the same exponent |
|
all of these statements are correct |
|
you can add monomials that have the same variable and the same exponent |
|
you can multiply monomials that have different variables and different exponents |
You can only add or subtract monomials that have the same variable and the same exponent. For example, 2a + 4a = 6a and 4a2 - a2 = 3a2 but 2a + 4b and 7a - 3b cannot be combined. However, you can multiply and divide monomials with unlike terms. For example, 2a x 6b = 12ab.
A cylinder with a radius (r) and a height (h) has a surface area of:
2(π r2) + 2π rh |
|
π r2h |
|
4π r2 |
|
π r2h2 |
A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The volume of a cylinder is π r2h and the surface area is 2(π r2) + 2π rh.