| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.81 |
| Score | 0% | 56% |
Solve for a:
-2a - 8 = -7 + 9a
| -\(\frac{1}{11}\) | |
| -\(\frac{1}{6}\) | |
| 1\(\frac{2}{5}\) | |
| \(\frac{3}{7}\) |
To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.
-2a - 8 = -7 + 9a
-2a = -7 + 9a + 8
-2a - 9a = -7 + 8
-11a = 1
a = \( \frac{1}{-11} \)
a = -\(\frac{1}{11}\)
If angle a = 32° and angle b = 25° what is the length of angle c?
| 74° | |
| 127° | |
| 107° | |
| 123° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 32° - 25° = 123°
A(n) __________ is to a parallelogram as a square is to a rectangle.
triangle |
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quadrilateral |
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rhombus |
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trapezoid |
A rhombus is a parallelogram with four equal-length sides. A square is a rectangle with four equal-length sides.
When two lines intersect, adjacent angles are __________ (they add up to 180°) and angles across from either other are __________ (they're equal).
obtuse, acute |
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vertical, supplementary |
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supplementary, vertical |
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acute, obtuse |
Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are supplementary (they add up to 180°) and angles across from either other are vertical (they're equal).
Which of the following is not required to define the slope-intercept equation for a line?
x-intercept |
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y-intercept |
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slope |
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\({\Delta y \over \Delta x}\) |
A line on the coordinate grid can be defined by a slope-intercept equation: y = mx + b. For a given value of x, the value of y can be determined given the slope (m) and y-intercept (b) of the line. The slope of a line is change in y over change in x, \({\Delta y \over \Delta x}\), and the y-intercept is the y-coordinate where the line crosses the vertical y-axis.