| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.16 |
| Score | 0% | 63% |
On this circle, a line segment connecting point A to point D is called:
radius |
|
chord |
|
diameter |
|
circumference |
A circle is a figure in which each point around its perimeter is an equal distance from the center. The radius of a circle is the distance between the center and any point along its perimeter. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).
If a = -7 and y = 4, what is the value of -9a(a - y)?
| -693 | |
| -9 | |
| -25 | |
| 70 |
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.)
-9a(a - y)
-9(-7)(-7 - 4)
-9(-7)(-11)
(63)(-11)
-693
If the area of this square is 81, what is the length of one of the diagonals?
| 4\( \sqrt{2} \) | |
| 5\( \sqrt{2} \) | |
| 3\( \sqrt{2} \) | |
| 9\( \sqrt{2} \) |
To find the diagonal we need to know the length of one of the square's sides. We know the area and the area of a square is the length of one side squared:
a = s2
so the length of one side of the square is:
s = \( \sqrt{a} \) = \( \sqrt{81} \) = 9
The Pythagorean theorem defines the square of the hypotenuse (diagonal) of a triangle with a right angle as the sum of the squares of the other two sides:
c2 = a2 + b2
c2 = 92 + 92
c2 = 162
c = \( \sqrt{162} \) = \( \sqrt{81 x 2} \) = \( \sqrt{81} \) \( \sqrt{2} \)
c = 9\( \sqrt{2} \)
Solve for x:
x2 - 6x + 23 = 5x - 1
| 2 or -3 | |
| -1 or -2 | |
| 7 or 3 | |
| 3 or 8 |
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:
x2 - 6x + 23 = 5x - 1
x2 - 6x + 23 + 1 = 5x
x2 - 6x - 5x + 24 = 0
x2 - 11x + 24 = 0
Next, factor the quadratic equation:
x2 - 11x + 24 = 0
(x - 3)(x - 8) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x - 3) or (x - 8) must equal zero:
If (x - 3) = 0, x must equal 3
If (x - 8) = 0, x must equal 8
So the solution is that x = 3 or 8
Which of the following expressions contains exactly two terms?
monomial |
|
quadratic |
|
binomial |
|
polynomial |
A monomial contains one term, a binomial contains two terms, and a polynomial contains more than two terms.