| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.72 |
| Score | 0% | 54% |
Solve for y:
y2 - 4y - 51 = -2y - 3
| 2 or -5 | |
| 3 or -2 | |
| -6 or 8 | |
| -6 or -9 |
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:
y2 - 4y - 51 = -2y - 3
y2 - 4y - 51 + 3 = -2y
y2 - 4y + 2y - 48 = 0
y2 - 2y - 48 = 0
Next, factor the quadratic equation:
y2 - 2y - 48 = 0
(y + 6)(y - 8) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (y + 6) or (y - 8) must equal zero:
If (y + 6) = 0, y must equal -6
If (y - 8) = 0, y must equal 8
So the solution is that y = -6 or 8
Which of the following statements about a parallelogram is not true?
opposite sides and adjacent angles are equal |
|
a parallelogram is a quadrilateral |
|
the perimeter of a parallelogram is the sum of the lengths of all sides |
|
the area of a parallelogram is base x height |
A parallelogram is a quadrilateral with two sets of parallel sides. Opposite sides (a = c, b = d) and angles (red = red, blue = blue) are equal. The area of a parallelogram is base x height and the perimeter is the sum of the lengths of all sides (a + b + c + d).
What is the circumference of a circle with a diameter of 15?
| 15π | |
| 38π | |
| 7π | |
| 6π |
The formula for circumference is circle diameter x π:
c = πd
c = 15π
On this circle, a line segment connecting point A to point D is called:
diameter |
|
chord |
|
radius |
|
circumference |
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 a triangle is not true?
exterior angle = sum of two adjacent interior angles |
|
area = ½bh |
|
perimeter = sum of side lengths |
|
sum of interior angles = 180° |
A triangle is a three-sided polygon. It has three interior angles that add up to 180° (a + b + c = 180°). An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite (d = b + c). The perimeter of a triangle is equal to the sum of the lengths of its three sides, the height of a triangle is equal to the length from the base to the opposite vertex (angle) and the area equals one-half triangle base x height: a = ½ base x height.