| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.09 |
| Score | 0% | 62% |
If a = -8 and z = 5, what is the value of 7a(a - z)?
| 27 | |
| 728 | |
| -40 | |
| -36 |
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.)
7a(a - z)
7(-8)(-8 - 5)
7(-8)(-13)
(-56)(-13)
728
Which types of triangles will always have at least two sides of equal length?
equilateral and right |
|
equilateral and isosceles |
|
equilateral, isosceles and right |
|
isosceles and right |
An isosceles triangle has two sides of equal length. An equilateral triangle has three sides of equal length. In a right triangle, two sides meet at a right angle.
Solve for a:
3a - 8 = -9 + 2a
| -3\(\frac{1}{2}\) | |
| \(\frac{2}{5}\) | |
| -1 | |
| -4 |
To solve this equation, 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.
3a - 8 = -9 + 2a
3a = -9 + 2a + 8
3a - 2a = -9 + 8
a = -1
What is the circumference of a circle with a radius of 8?
| 2π | |
| 17π | |
| 4π | |
| 16π |
The formula for circumference is circle diameter x π. Circle diameter is 2 x radius:
c = πd
c = π(2 * r)
c = π(2 * 8)
c = 16π
Solve for x:
x2 + 4x - 12 = 0
| -1 or -8 | |
| -3 or -8 | |
| 2 or -6 | |
| 9 or -8 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
x2 + 4x - 12 = 0
(x - 2)(x + 6) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x - 2) or (x + 6) must equal zero:
If (x - 2) = 0, x must equal 2
If (x + 6) = 0, x must equal -6
So the solution is that x = 2 or -6