| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.14 |
| Score | 0% | 63% |
What is 9a - 4a?
| 5 | |
| 13a2 | |
| a2 | |
| 5a |
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.
9a - 4a = 5a
Which of the following statements about a parallelogram is not true?
opposite sides and adjacent angles are equal |
|
the perimeter of a parallelogram is the sum of the lengths of all sides |
|
the area of a parallelogram is base x height |
|
a parallelogram is a quadrilateral |
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 - 7a + 26 = 3a + 2
| 4 or 6 | |
| 6 or -6 | |
| 9 or 3 | |
| -4 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 - 7a + 26 = 3a + 2
a2 - 7a + 26 - 2 = 3a
a2 - 7a - 3a + 24 = 0
a2 - 10a + 24 = 0
Next, factor the quadratic equation:
a2 - 10a + 24 = 0
(a - 4)(a - 6) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (a - 4) or (a - 6) must equal zero:
If (a - 4) = 0, a must equal 4
If (a - 6) = 0, a must equal 6
So the solution is that a = 4 or 6
If a = c = 4, b = d = 8, and the blue angle = 56°, what is the area of this parallelogram?
| 35 | |
| 32 | |
| 10 | |
| 24 |
The area of a parallelogram is equal to its length x width:
a = l x w
a = a x b
a = 4 x 8
a = 32
What is the circumference of a circle with a radius of 15?
| 30π | |
| 16π | |
| 2π | |
| 36π |
The formula for circumference is circle diameter x π. Circle diameter is 2 x radius:
c = πd
c = π(2 * r)
c = π(2 * 15)
c = 30π