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Solve for c:
c2 + 3c - 28 = 5c - 4
-2 or -7 | |
-4 or -7 | |
-4 or 6 | |
-3 or -6 |
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:
c2 + 3c - 28 = 5c - 4
c2 + 3c - 28 + 4 = 5c
c2 + 3c - 5c - 24 = 0
c2 - 2c - 24 = 0
Next, factor the quadratic equation:
c2 - 2c - 24 = 0
(c + 4)(c - 6) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (c + 4) or (c - 6) must equal zero:
If (c + 4) = 0, c must equal -4
If (c - 6) = 0, c must equal 6
So the solution is that c = -4 or 6
On this circle, line segment CD is the:
radius |
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circumference |
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diameter |
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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).
Which of the following statements about math operations is incorrect?
you can subtract monomials that have the same variable and the same exponent |
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you can add monomials that have the same variable and the same exponent |
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you can multiply monomials that have different variables and different exponents |
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all of these statements are correct |
You can only add or subtract monomials that have the same variable and the same exponent. For example, 2a + 4a = 6a and 4a2 - a2 = 3a2 but 2a + 4b and 7a - 3b cannot be combined. However, you can multiply and divide monomials with unlike terms. For example, 2a x 6b = 12ab.
If the area of this square is 1, what is the length of one of the diagonals?
6\( \sqrt{2} \) | |
5\( \sqrt{2} \) | |
\( \sqrt{2} \) | |
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 = \( \sqrt{a} \) = \( \sqrt{1} \) = 1
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 = 12 + 12
c2 = 2
c = \( \sqrt{2} \)
Solve for y:
-3y + 7 = -9 + y
1\(\frac{1}{3}\) | |
-2 | |
1\(\frac{1}{2}\) | |
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.
-3y + 7 = -9 + y
-3y = -9 + y - 7
-3y - y = -9 - 7
-4y = -16
y = \( \frac{-16}{-4} \)
y = 4