| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.66 |
| Score | 0% | 53% |
Simplify (y + 5)(y + 2)
| y2 - 3y - 10 | |
| y2 + 3y - 10 | |
| y2 - 7y + 10 | |
| y2 + 7y + 10 |
To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:
(y + 5)(y + 2)
(y x y) + (y x 2) + (5 x y) + (5 x 2)
y2 + 2y + 5y + 10
y2 + 7y + 10
Factor y2 + 4y - 5
| (y - 1)(y - 5) | |
| (y - 1)(y + 5) | |
| (y + 1)(y - 5) | |
| (y + 1)(y + 5) |
To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce -5 as well and sum (Inside, Outside) to equal 4. For this problem, those two numbers are -1 and 5. Then, plug these into a set of binomials using the square root of the First variable (y2):
y2 + 4y - 5
y2 + (-1 + 5)y + (-1 x 5)
(y - 1)(y + 5)
Solve 6b + 3b = -7b + z - 2 for b in terms of z.
| -\(\frac{1}{4}\)z + 1\(\frac{1}{2}\) | |
| 8\(\frac{1}{2}\)z + 1 | |
| -1\(\frac{3}{8}\)z - \(\frac{3}{4}\) | |
| -\(\frac{2}{13}\)z - \(\frac{2}{13}\) |
To solve this equation, isolate the variable for which you are solving (b) on one side of the equation and put everything else on the other side.
6b + 3z = -7b + z - 2
6b = -7b + z - 2 - 3z
6b + 7b = z - 2 - 3z
13b = -2z - 2
b = \( \frac{-2z - 2}{13} \)
b = \( \frac{-2z}{13} \) + \( \frac{-2}{13} \)
b = -\(\frac{2}{13}\)z - \(\frac{2}{13}\)
Which of the following statements about a triangle is not true?
area = ½bh |
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sum of interior angles = 180° |
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exterior angle = sum of two adjacent interior angles |
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perimeter = sum of side lengths |
A triangle is a three-sided polygon. It has three interior angles that add up to 180° (a + b + c = 180°). An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite (d = b + c). The perimeter of a triangle is equal to the sum of the lengths of its three sides, the height of a triangle is equal to the length from the base to the opposite vertex (angle) and the area equals one-half triangle base x height: a = ½ base x height.
Solve for y:
y2 - 12y + 27 = 0
| 3 or 9 | |
| 6 or -3 | |
| -1 or -4 | |
| 7 or 5 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
y2 - 12y + 27 = 0
(y - 3)(y - 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (y - 3) or (y - 9) must equal zero:
If (y - 3) = 0, y must equal 3
If (y - 9) = 0, y must equal 9
So the solution is that y = 3 or 9