| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.72 |
| Score | 0% | 74% |
Which of the following statements about math operations is incorrect?
all of these statements are correct |
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you can multiply monomials that have different variables and different exponents |
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you can add monomials that have the same variable and the same exponent |
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you can subtract 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.
What is 4a3 + 5a3?
| a36 | |
| -1 | |
| 9a3 | |
| -a6 |
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.
4a3 + 5a3 = 9a3
What is the area of a circle with a radius of 4?
| 81π | |
| 9π | |
| 16π | |
| 64π |
The formula for area is πr2:
a = πr2
a = π(42)
a = 16π
A quadrilateral is a shape with __________ sides.
2 |
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3 |
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5 |
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4 |
A quadrilateral is a shape with four sides. The perimeter of a quadrilateral is the sum of the lengths of its four sides.
If side a = 6, side b = 8, what is the length of the hypotenuse of this right triangle?
| 10 | |
| \( \sqrt{53} \) | |
| \( \sqrt{45} \) | |
| \( \sqrt{50} \) |
According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:
c2 = a2 + b2
c2 = 62 + 82
c2 = 36 + 64
c2 = 100
c = \( \sqrt{100} \)
c = 10