| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.79 |
| Score | 0% | 56% |
Solve for c:
c2 - 2c + 0 = -3c + 2
| 9 or -9 | |
| 1 or -2 | |
| 8 or -3 | |
| 6 or -5 |
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 - 2c + 0 = -3c + 2
c2 - 2c + 0 - 2 = -3c
c2 - 2c + 3c - 2 = 0
c2 + c - 2 = 0
Next, factor the quadratic equation:
c2 + c - 2 = 0
(c - 1)(c + 2) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (c - 1) or (c + 2) must equal zero:
If (c - 1) = 0, c must equal 1
If (c + 2) = 0, c must equal -2
So the solution is that c = 1 or -2
A(n) __________ is two expressions separated by an equal sign.
equation |
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expression |
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problem |
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formula |
An equation is two expressions separated by an equal sign. The key to solving equations is to 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.
A(n) __________ is to a parallelogram as a square is to a rectangle.
quadrilateral |
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trapezoid |
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triangle |
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rhombus |
A rhombus is a parallelogram with four equal-length sides. A square is a rectangle with four equal-length sides.
The formula for the area of a circle is which of the following?
c = π r |
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c = π d2 |
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c = π r2 |
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c = π d |
The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)2 : a = π r2.
If a = c = 8, b = d = 9, what is the area of this rectangle?
| 12 | |
| 72 | |
| 36 | |
| 6 |
The area of a rectangle is equal to its length x width:
a = l x w
a = a x b
a = 8 x 9
a = 72