| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.41 |
| Score | 0% | 68% |
What is 2a + 8a?
| -6a2 | |
| 10a | |
| a2 | |
| 16a |
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.
2a + 8a = 10a
The dimensions of this cylinder are height (h) = 8 and radius (r) = 2. What is the surface area?
| 16π | |
| 40π | |
| 112π | |
| 4π |
The surface area of a cylinder is 2πr2 + 2πrh:
sa = 2πr2 + 2πrh
sa = 2π(22) + 2π(2 x 8)
sa = 2π(4) + 2π(16)
sa = (2 x 4)π + (2 x 16)π
sa = 8π + 32π
sa = 40π
If a = -5 and x = 3, what is the value of -2a(a - x)?
| 324 | |
| 36 | |
| -80 | |
| 12 |
To solve this equation, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)
-2a(a - x)
-2(-5)(-5 - 3)
-2(-5)(-8)
(10)(-8)
-80
Simplify 3a x 7b.
| 21\( \frac{a}{b} \) | |
| 21\( \frac{b}{a} \) | |
| 21a2b2 | |
| 21ab |
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.
3a x 7b = (3 x 7) (a x b) = 21ab
If the base of this triangle is 3 and the height is 4, what is the area?
| 39 | |
| 35 | |
| 6 | |
| 71\(\frac{1}{2}\) |
The area of a triangle is equal to ½ base x height:
a = ½bh
a = ½ x 3 x 4 = \( \frac{12}{2} \) = 6