| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.09 |
| Score | 0% | 62% |
Which of the following is not true about both rectangles and squares?
all interior angles are right angles |
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the area is length x width |
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the perimeter is the sum of the lengths of all four sides |
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the lengths of all sides are equal |
A rectangle is a parallelogram containing four right angles. Opposite sides (a = c, b = d) are equal and the perimeter is the sum of the lengths of all sides (a + b + c + d) or, comonly, 2 x length x width. The area of a rectangle is length x width. A square is a rectangle with four equal length sides. The perimeter of a square is 4 x length of one side (4s) and the area is the length of one side squared (s2).
Solve for c:
9c + 2 = -9 + 6c
| 1 | |
| \(\frac{5}{8}\) | |
| -3\(\frac{2}{3}\) | |
| -1 |
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.
9c + 2 = -9 + 6c
9c = -9 + 6c - 2
9c - 6c = -9 - 2
3c = -11
c = \( \frac{-11}{3} \)
c = -3\(\frac{2}{3}\)
Which of the following statements about a parallelogram is not true?
a parallelogram is a quadrilateral |
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the perimeter of a parallelogram is the sum of the lengths of all sides |
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the area of a parallelogram is base x height |
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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).
Solve for a:
a2 + 18a + 52 = 3a - 2
| 4 or -2 | |
| 2 or -5 | |
| -3 or -6 | |
| -6 or -9 |
The first step to solve a quadratic expression that's not set to zero is to solve the equation so that it is set to zero:
a2 + 18a + 52 = 3a - 2
a2 + 18a + 52 + 2 = 3a
a2 + 18a - 3a + 54 = 0
a2 + 15a + 54 = 0
Next, factor the quadratic equation:
a2 + 15a + 54 = 0
(a + 6)(a + 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (a + 6) or (a + 9) must equal zero:
If (a + 6) = 0, a must equal -6
If (a + 9) = 0, a must equal -9
So the solution is that a = -6 or -9
If a = 8, b = 6, c = 6, and d = 2, what is the perimeter of this quadrilateral?
| 18 | |
| 20 | |
| 23 | |
| 22 |
Perimeter is equal to the sum of the four sides:
p = a + b + c + d
p = 8 + 6 + 6 + 2
p = 22