| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.46 |
| Score | 0% | 69% |
The formula for the area of a circle is which of the following?
a = π r2 |
|
a = π r |
|
a = π d |
|
a = π d2 |
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.
Simplify (3a)(2ab) + (7a2)(6b).
| 48a2b | |
| 36a2b | |
| -36ab2 | |
| 65ab2 |
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)(2ab) + (7a2)(6b)
(3 x 2)(a x a x b) + (7 x 6)(a2 x b)
(6)(a1+1 x b) + (42)(a2b)
6a2b + 42a2b
48a2b
If the base of this triangle is 3 and the height is 9, what is the area?
| 27 | |
| 90 | |
| 24\(\frac{1}{2}\) | |
| 13\(\frac{1}{2}\) |
The area of a triangle is equal to ½ base x height:
a = ½bh
a = ½ x 3 x 9 = \( \frac{27}{2} \) = 13\(\frac{1}{2}\)
If side a = 8, side b = 5, what is the length of the hypotenuse of this right triangle?
| \( \sqrt{89} \) | |
| \( \sqrt{52} \) | |
| \( \sqrt{5} \) | |
| \( \sqrt{37} \) |
According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:
c2 = a2 + b2
c2 = 82 + 52
c2 = 64 + 25
c2 = 89
c = \( \sqrt{89} \)
What is 5a + 9a?
| 45a | |
| 45a2 | |
| 14a | |
| a2 |
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.
5a + 9a = 14a