| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.08 |
| Score | 0% | 62% |
If angle a = 23° and angle b = 49° what is the length of angle d?
| 133° | |
| 157° | |
| 137° | |
| 122° |
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° - 23° - 49° = 108°
So, d° = 49° + 108° = 157°
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° - 23° = 157°
If angle a = 57° and angle b = 43° what is the length of angle c?
| 133° | |
| 80° | |
| 86° | |
| 79° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 57° - 43° = 80°
What is 4a - 5a?
| -a2 | |
| -1 | |
| 20a2 | |
| -1a |
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.
4a - 5a = -1a
Which of the following statements about a parallelogram is not true?
the perimeter of a parallelogram is the sum of the lengths of all sides |
|
a parallelogram is a quadrilateral |
|
the area of a parallelogram is base x height |
|
opposite sides and adjacent angles are equal |
A parallelogram is a quadrilateral with two sets of parallel sides. Opposite sides (a = c, b = d) and angles (red = red, blue = blue) are equal. The area of a parallelogram is base x height and the perimeter is the sum of the lengths of all sides (a + b + c + d).
The dimensions of this cube are height (h) = 8, length (l) = 5, and width (w) = 5. What is the surface area?
| 54 | |
| 286 | |
| 210 | |
| 58 |
The surface area of a cube is (2 x length x width) + (2 x width x height) + (2 x length x height):
sa = 2lw + 2wh + 2lh
sa = (2 x 5 x 5) + (2 x 5 x 8) + (2 x 5 x 8)
sa = (50) + (80) + (80)
sa = 210