| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.04 |
| Score | 0% | 61% |
Solve for x:
x2 - 59 = x - 3
| -2 or -9 | |
| 5 or 4 | |
| -7 or 8 | |
| -2 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:
x2 - 59 = x - 3
x2 - 59 + 3 = x
x2 - x - 56 = 0
x2 - x - 56 = 0
Next, factor the quadratic equation:
x2 - x - 56 = 0
(x + 7)(x - 8) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x + 7) or (x - 8) must equal zero:
If (x + 7) = 0, x must equal -7
If (x - 8) = 0, x must equal 8
So the solution is that x = -7 or 8
Breaking apart a quadratic expression into a pair of binomials is called:
deconstructing |
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squaring |
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factoring |
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normalizing |
To factor a quadratic expression, apply the FOIL (First, Outside, Inside, Last) method in reverse.
Simplify (6a)(7ab) + (2a2)(4b).
| 50a2b | |
| 78a2b | |
| 78ab2 | |
| 34a2b |
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.
(6a)(7ab) + (2a2)(4b)
(6 x 7)(a x a x b) + (2 x 4)(a2 x b)
(42)(a1+1 x b) + (8)(a2b)
42a2b + 8a2b
50a2b
If the area of this square is 49, what is the length of one of the diagonals?
| 8\( \sqrt{2} \) | |
| 7\( \sqrt{2} \) | |
| 2\( \sqrt{2} \) | |
| \( \sqrt{2} \) |
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 = \( \sqrt{a} \) = \( \sqrt{49} \) = 7
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 = 72 + 72
c2 = 98
c = \( \sqrt{98} \) = \( \sqrt{49 x 2} \) = \( \sqrt{49} \) \( \sqrt{2} \)
c = 7\( \sqrt{2} \)
On this circle, a line segment connecting point A to point D is called:
radius |
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chord |
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circumference |
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diameter |
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).