| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.85 |
| Score | 0% | 57% |
Solve for z:
z2 - 5z - 46 = -4z - 4
| -6 or -9 | |
| 7 or 3 | |
| 8 or 5 | |
| -6 or 7 |
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:
z2 - 5z - 46 = -4z - 4
z2 - 5z - 46 + 4 = -4z
z2 - 5z + 4z - 42 = 0
z2 - z - 42 = 0
Next, factor the quadratic equation:
z2 - z - 42 = 0
(z + 6)(z - 7) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (z + 6) or (z - 7) must equal zero:
If (z + 6) = 0, z must equal -6
If (z - 7) = 0, z must equal 7
So the solution is that z = -6 or 7
The formula for the area of a circle is which of the following?
a = π d2 |
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a = π r |
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a = π d |
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a = π r2 |
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.
A(n) __________ is to a parallelogram as a square is to a rectangle.
trapezoid |
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triangle |
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rhombus |
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quadrilateral |
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 d |
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c = π d2 |
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c = π r2 |
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c = π r |
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.
Which of the following expressions contains exactly two terms?
quadratic |
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monomial |
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polynomial |
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binomial |
A monomial contains one term, a binomial contains two terms, and a polynomial contains more than two terms.