| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.98 |
| Score | 0% | 60% |
Which of the following statements about math operations is incorrect?
you can subtract monomials that have the same variable and the same exponent |
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you can multiply monomials that have different variables and different exponents |
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all of these statements are correct |
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you can add monomials that have the same variable and the same exponent |
You can only add or subtract monomials that have the same variable and the same exponent. For example, 2a + 4a = 6a and 4a2 - a2 = 3a2 but 2a + 4b and 7a - 3b cannot be combined. However, you can multiply and divide monomials with unlike terms. For example, 2a x 6b = 12ab.
On this circle, a line segment connecting point A to point D is called:
circumference |
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diameter |
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chord |
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radius |
A circle is a figure in which each point around its perimeter is an equal distance from the center. The radius of a circle is the distance between the center and any point along its perimeter. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).
A(n) __________ is to a parallelogram as a square is to a rectangle.
quadrilateral |
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triangle |
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trapezoid |
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rhombus |
A rhombus is a parallelogram with four equal-length sides. A square is a rectangle with four equal-length sides.
If a = c = 7, b = d = 6, what is the area of this rectangle?
| 18 | |
| 42 | |
| 28 | |
| 30 |
The area of a rectangle is equal to its length x width:
a = l x w
a = a x b
a = 7 x 6
a = 42
Solve for a:
a2 - 59 = -2a + 4
| 9 or -3 | |
| 7 or -9 | |
| 8 or 4 | |
| 7 or -7 |
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 - 59 = -2a + 4
a2 - 59 - 4 = -2a
a2 + + 2a - 63 = 0
a2 + 2a - 63 = 0
Next, factor the quadratic equation:
a2 + 2a - 63 = 0
(a - 7)(a + 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (a - 7) or (a + 9) must equal zero:
If (a - 7) = 0, a must equal 7
If (a + 9) = 0, a must equal -9
So the solution is that a = 7 or -9