| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.86 |
| Score | 0% | 57% |
The formula for the area of a circle is which of the following?
a = π r2 |
|
a = π d2 |
|
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.
The dimensions of this cylinder are height (h) = 8 and radius (r) = 7. What is the surface area?
| 210π | |
| 272π | |
| 70π | |
| 140π |
The surface area of a cylinder is 2πr2 + 2πrh:
sa = 2πr2 + 2πrh
sa = 2π(72) + 2π(7 x 8)
sa = 2π(49) + 2π(56)
sa = (2 x 49)π + (2 x 56)π
sa = 98π + 112π
sa = 210π
The formula for the area of a circle is which of the following?
c = π d |
|
c = π r |
|
c = π r2 |
|
c = 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.
Which of the following statements about a triangle is not true?
area = ½bh |
|
perimeter = sum of side lengths |
|
exterior angle = sum of two adjacent interior angles |
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sum of interior angles = 180° |
A triangle is a three-sided polygon. It has three interior angles that add up to 180° (a + b + c = 180°). An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite (d = b + c). The perimeter of a triangle is equal to the sum of the lengths of its three sides, the height of a triangle is equal to the length from the base to the opposite vertex (angle) and the area equals one-half triangle base x height: a = ½ base x height.
What is 5a - 8a?
| -3a2 | |
| -3a | |
| 13a2 | |
| 13 |
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 - 8a = -3a