| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.11 |
| Score | 0% | 62% |
If b = -3 and z = -6, what is the value of 8b(b - z)?
| 220 | |
| -72 | |
| -16 | |
| -42 |
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.)
8b(b - z)
8(-3)(-3 + 6)
8(-3)(3)
(-24)(3)
-72
What is 7a3 - 2a3?
| 5a3 | |
| 14a3 | |
| 5 | |
| 14a6 |
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.
7a3 - 2a3 = 5a3
A cylinder with a radius (r) and a height (h) has a surface area of:
π r2h |
|
4π r2 |
|
2(π r2) + 2π rh |
|
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.
If angle a = 40° and angle b = 28° what is the length of angle d?
| 121° | |
| 115° | |
| 138° | |
| 140° |
An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite:
d° = b° + c°
To find angle c, remember that the sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 40° - 28° = 112°
So, d° = 28° + 112° = 140°
A shortcut to get this answer is to remember that angles around a line add up to 180°:
a° + d° = 180°
d° = 180° - a°
d° = 180° - 40° = 140°
Which of the following statements about a triangle is not true?
exterior angle = sum of two adjacent interior angles |
|
area = ½bh |
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sum of interior angles = 180° |
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perimeter = sum of side lengths |
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.