| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.02 |
| Score | 0% | 60% |
Factor y2 - 3y - 18
| (y - 6)(y - 3) | |
| (y + 6)(y - 3) | |
| (y + 6)(y + 3) | |
| (y - 6)(y + 3) |
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 -18 as well and sum (Inside, Outside) to equal -3. For this problem, those two numbers are -6 and 3. Then, plug these into a set of binomials using the square root of the First variable (y2):
y2 - 3y - 18
y2 + (-6 + 3)y + (-6 x 3)
(y - 6)(y + 3)
A(n) __________ is two expressions separated by an equal sign.
formula |
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problem |
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equation |
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expression |
An equation is two expressions separated by an equal sign. The key to solving equations is to repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.
If c = -1 and z = 3, what is the value of -4c(c - z)?
| 100 | |
| 390 | |
| -96 | |
| -16 |
To solve this equation, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)
-4c(c - z)
-4(-1)(-1 - 3)
-4(-1)(-4)
(4)(-4)
-16
If angle a = 56° and angle b = 64° what is the length of angle c?
| 89° | |
| 72° | |
| 94° | |
| 60° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 56° - 64° = 60°
Solve -2a + 3a = -8a - 8y - 1 for a in terms of y.
| y - 2 | |
| -1\(\frac{1}{3}\)y + 1\(\frac{1}{2}\) | |
| -1\(\frac{5}{6}\)y - \(\frac{1}{6}\) | |
| \(\frac{2}{5}\)y + 1\(\frac{3}{5}\) |
To solve this equation, isolate the variable for which you are solving (a) on one side of the equation and put everything else on the other side.
-2a + 3y = -8a - 8y - 1
-2a = -8a - 8y - 1 - 3y
-2a + 8a = -8y - 1 - 3y
6a = -11y - 1
a = \( \frac{-11y - 1}{6} \)
a = \( \frac{-11y}{6} \) + \( \frac{-1}{6} \)
a = -1\(\frac{5}{6}\)y - \(\frac{1}{6}\)