| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.89 |
| Score | 0% | 58% |
Simplify (2a)(6ab) + (4a2)(3b).
| 24ab2 | |
| 56a2b | |
| b2 | |
| 24a2b |
To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.
(2a)(6ab) + (4a2)(3b)
(2 x 6)(a x a x b) + (4 x 3)(a2 x b)
(12)(a1+1 x b) + (12)(a2b)
12a2b + 12a2b
24a2b
Which of the following statements about a parallelogram is not true?
a parallelogram is a quadrilateral |
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opposite sides and adjacent angles are equal |
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the area of a parallelogram is base x height |
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the perimeter of a parallelogram is the sum of the lengths of all sides |
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 formula for the area of a circle is which of the following?
c = π r |
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c = π r2 |
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c = π d2 |
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c = π d |
The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)2 : a = π r2.
The dimensions of this cube are height (h) = 9, length (l) = 6, and width (w) = 3. What is the volume?
| 135 | |
| 84 | |
| 162 | |
| 216 |
The volume of a cube is height x length x width:
v = h x l x w
v = 9 x 6 x 3
v = 162
If the area of this square is 49, what is the length of one of the diagonals?
| 7\( \sqrt{2} \) | |
| \( \sqrt{2} \) | |
| 2\( \sqrt{2} \) | |
| 5\( \sqrt{2} \) |
To find the diagonal we need to know the length of one of the square's sides. We know the area and the area of a square is the length of one side squared:
a = s2
so the length of one side of the square is:
s = \( \sqrt{a} \) = \( \sqrt{49} \) = 7
The Pythagorean theorem defines the square of the hypotenuse (diagonal) of a triangle with a right angle as the sum of the squares of the other two sides:
c2 = a2 + b2
c2 = 72 + 72
c2 = 98
c = \( \sqrt{98} \) = \( \sqrt{49 x 2} \) = \( \sqrt{49} \) \( \sqrt{2} \)
c = 7\( \sqrt{2} \)