| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.23 |
| Score | 0% | 45% |
Solve for a:
a2 - 16a + 35 = -4a + 3
| 4 or 8 | |
| -1 or -2 | |
| 3 or -2 | |
| 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:
a2 - 16a + 35 = -4a + 3
a2 - 16a + 35 - 3 = -4a
a2 - 16a + 4a + 32 = 0
a2 - 12a + 32 = 0
Next, factor the quadratic equation:
a2 - 12a + 32 = 0
(a - 4)(a - 8) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (a - 4) or (a - 8) must equal zero:
If (a - 4) = 0, a must equal 4
If (a - 8) = 0, a must equal 8
So the solution is that a = 4 or 8
The formula for the area of a circle is which of the following?
c = π r2 |
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c = π d2 |
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c = π d |
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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 statements about parallel lines with a transversal is not correct?
all acute angles equal each other |
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all of the angles formed by a transversal are called interior angles |
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same-side interior angles are complementary and equal each other |
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angles in the same position on different parallel lines are called corresponding angles |
Parallel lines are lines that share the same slope (steepness) and therefore never intersect. A transversal occurs when a set of parallel lines are crossed by another line. All of the angles formed by a transversal are called interior angles and angles in the same position on different parallel lines equal each other (a° = w°, b° = x°, c° = z°, d° = y°) and are called corresponding angles. Alternate interior angles are equal (a° = z°, b° = y°, c° = w°, d° = x°) and all acute angles (a° = c° = w° = z°) and all obtuse angles (b° = d° = x° = y°) equal each other. Same-side interior angles are supplementary and add up to 180° (e.g. a° + d° = 180°, d° + c° = 180°).
Find the value of c:
6c + x = -2
9c - 3x = -1
| 2\(\frac{3}{4}\) | |
| 1\(\frac{1}{4}\) | |
| -1\(\frac{19}{42}\) | |
| -\(\frac{7}{27}\) |
You need to find the value of c so solve the first equation in terms of x:
6c + x = -2
x = -2 - 6c
then substitute the result (-2 - 6c) into the second equation:
9c - 3(-2 - 6c) = -1
9c + (-3 x -2) + (-3 x -6c) = -1
9c + 6 + 18c = -1
9c + 18c = -1 - 6
27c = -7
c = \( \frac{-7}{27} \)
c = -\(\frac{7}{27}\)
This diagram represents two parallel lines with a transversal. If x° = 164, what is the value of w°?
| 16 | |
| 160 | |
| 157 | |
| 39 |
For parallel lines with a transversal, the following relationships apply:
Applying these relationships starting with x° = 164, the value of w° is 16.