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Solve for x:
x2 - x - 70 = -2x + 2
| 8 or -1 | |
| 8 or -9 | |
| -5 or -5 | |
| 8 or 3 |
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 - x - 70 = -2x + 2
x2 - x - 70 - 2 = -2x
x2 - x + 2x - 72 = 0
x2 + x - 72 = 0
Next, factor the quadratic equation:
x2 + x - 72 = 0
(x - 8)(x + 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x - 8) or (x + 9) must equal zero:
If (x - 8) = 0, x must equal 8
If (x + 9) = 0, x must equal -9
So the solution is that x = 8 or -9
Simplify (y + 5)(y - 2)
| y2 - 3y - 10 | |
| y2 - 7y + 10 | |
| y2 + 3y - 10 | |
| y2 + 7y + 10 |
To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:
(y + 5)(y - 2)
(y x y) + (y x -2) + (5 x y) + (5 x -2)
y2 - 2y + 5y - 10
y2 + 3y - 10
The endpoints of this line segment are at (-2, -2) and (2, 0). What is the slope-intercept equation for this line?
| y = -3x + 3 | |
| y = -2x + 4 | |
| y = \(\frac{1}{2}\)x - 1 | |
| y = -1\(\frac{1}{2}\)x + 4 |
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 -1. 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, -2) and (2, 0) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(0.0) - (-2.0)}{(2) - (-2)} \) = \( \frac{2}{4} \)Plugging these values into the slope-intercept equation:
y = \(\frac{1}{2}\)x - 1
On this circle, line segment CD is the:
radius |
|
circumference |
|
diameter |
|
chord |
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).
What is 2a + 2a?
| 4a | |
| a2 | |
| 0 | |
| 2 |
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 + 2a = 4a