| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.67 |
| Score | 0% | 73% |
Solve for z:
z2 + 7z - 3 = 4z + 1
| -2 or -3 | |
| 9 or -2 | |
| 4 or -8 | |
| 1 or -4 |
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:
z2 + 7z - 3 = 4z + 1
z2 + 7z - 3 - 1 = 4z
z2 + 7z - 4z - 4 = 0
z2 + 3z - 4 = 0
Next, factor the quadratic equation:
z2 + 3z - 4 = 0
(z - 1)(z + 4) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (z - 1) or (z + 4) must equal zero:
If (z - 1) = 0, z must equal 1
If (z + 4) = 0, z must equal -4
So the solution is that z = 1 or -4
Simplify 8a x 2b.
| 10ab | |
| 16\( \frac{b}{a} \) | |
| 16ab | |
| 16\( \frac{a}{b} \) |
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.
8a x 2b = (8 x 2) (a x b) = 16ab
A coordinate grid is composed of which of the following?
x-axis |
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origin |
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all of these |
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y-axis |
The coordinate grid is composed of a horizontal x-axis and a vertical y-axis. The center of the grid, where the x-axis and y-axis meet, is called the origin.
What is 2a - 6a?
| -4a2 | |
| -4a | |
| 12a | |
| 8a2 |
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.
2a - 6a = -4a
Which of the following is not true about both rectangles and squares?
the perimeter is the sum of the lengths of all four sides |
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the lengths of all sides are equal |
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the area is length x width |
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all interior angles are right angles |
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).