| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.73 |
| Score | 0% | 55% |
Simplify (2a)(7ab) + (2a2)(2b).
| -10ab2 | |
| 18a2b | |
| 18ab2 | |
| 10ab2 |
To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.
(2a)(7ab) + (2a2)(2b)
(2 x 7)(a x a x b) + (2 x 2)(a2 x b)
(14)(a1+1 x b) + (4)(a2b)
14a2b + 4a2b
18a2b
The endpoints of this line segment are at (-2, -1) and (2, -7). What is the slope-intercept equation for this line?
| y = -1\(\frac{1}{2}\)x - 4 | |
| y = -2x - 2 | |
| y = x - 1 | |
| y = 2\(\frac{1}{2}\)x + 1 |
The slope-intercept equation for a line is y = mx + b where m is the slope and b is the y-intercept of the line. From the graph, you can see that the y-intercept (the y-value from the point where the line crosses the y-axis) is -4. The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, -1) and (2, -7) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-7.0) - (-1.0)}{(2) - (-2)} \) = \( \frac{-6}{4} \)Plugging these values into the slope-intercept equation:
y = -1\(\frac{1}{2}\)x - 4
The dimensions of this cylinder are height (h) = 8 and radius (r) = 4. What is the volume?
| 128π | |
| 75π | |
| 180π | |
| 24π |
The volume of a cylinder is πr2h:
v = πr2h
v = π(42 x 8)
v = 128π
On this circle, line segment CD is the:
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).
Solve for y:
y2 + 12y + 35 = 0
| 7 or 2 | |
| 2 or -8 | |
| 8 or 5 | |
| -5 or -7 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
y2 + 12y + 35 = 0
(y + 5)(y + 7) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (y + 5) or (y + 7) must equal zero:
If (y + 5) = 0, y must equal -5
If (y + 7) = 0, y must equal -7
So the solution is that y = -5 or -7