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Solve for a:
a2 - 10a - 17 = -3a + 1
| -2 or -3 | |
| -2 or 9 | |
| 7 or 6 | |
| 1 or -2 |
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:
a2 - 10a - 17 = -3a + 1
a2 - 10a - 17 - 1 = -3a
a2 - 10a + 3a - 18 = 0
a2 - 7a - 18 = 0
Next, factor the quadratic equation:
a2 - 7a - 18 = 0
(a + 2)(a - 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (a + 2) or (a - 9) must equal zero:
If (a + 2) = 0, a must equal -2
If (a - 9) = 0, a must equal 9
So the solution is that a = -2 or 9
If side a = 7, side b = 3, what is the length of the hypotenuse of this right triangle?
| \( \sqrt{98} \) | |
| \( \sqrt{58} \) | |
| \( \sqrt{18} \) | |
| \( \sqrt{82} \) |
According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:
c2 = a2 + b2
c2 = 72 + 32
c2 = 49 + 9
c2 = 58
c = \( \sqrt{58} \)
What is 7a + 2a?
| 9a | |
| 5 | |
| a2 | |
| 14a2 |
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.
7a + 2a = 9a
On this circle, a line segment connecting point A to point D is called:
diameter |
|
chord |
|
circumference |
|
radius |
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 -5a + 5a = -2a + 7y - 9 for a in terms of y.
| 1\(\frac{5}{6}\)y + 1\(\frac{1}{6}\) | |
| 1\(\frac{1}{2}\)y - 4 | |
| -2\(\frac{2}{3}\)y + 2\(\frac{2}{3}\) | |
| -\(\frac{2}{3}\)y + 3 |
To solve this equation, isolate the variable for which you are solving (a) on one side of the equation and put everything else on the other side.
-5a + 5y = -2a + 7y - 9
-5a = -2a + 7y - 9 - 5y
-5a + 2a = 7y - 9 - 5y
-3a = 2y - 9
a = \( \frac{2y - 9}{-3} \)
a = \( \frac{2y}{-3} \) + \( \frac{-9}{-3} \)
a = -\(\frac{2}{3}\)y + 3