| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.69 |
| Score | 0% | 74% |
If a = 7 and x = -7, what is the value of 6a(a - x)?
| 588 | |
| 12 | |
| 144 | |
| 72 |
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.)
6a(a - x)
6(7)(7 + 7)
6(7)(14)
(42)(14)
588
What is the circumference of a circle with a diameter of 19?
| 12π | |
| 16π | |
| 19π | |
| 15π |
The formula for circumference is circle diameter x π:
c = πd
c = 19π
A right angle measures:
45° |
|
90° |
|
180° |
|
360° |
A right angle measures 90 degrees and is the intersection of two perpendicular lines. In diagrams, a right angle is indicated by a small box completing a square with the perpendicular lines.
What is 2a + 8a?
| 16a2 | |
| 10a | |
| 10a2 | |
| -6a2 |
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 + 8a = 10a
Solve for z:
z2 - 12z + 27 = 0
| -1 or -8 | |
| 3 or 9 | |
| -6 or -8 | |
| -5 or -8 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
z2 - 12z + 27 = 0
(z - 3)(z - 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (z - 3) or (z - 9) must equal zero:
If (z - 3) = 0, z must equal 3
If (z - 9) = 0, z must equal 9
So the solution is that z = 3 or 9