In parallelogram ABCD , diagonals AC¯¯¯¯¯ and BD¯¯¯¯¯ intersect at point E, BE=2x2−x , and DE=x2+6 . What is BD ?
2 answers:
Refer to the diagram shown below.
BE = 2x² - x
DE = x² + 6
The intersecting diagonals bisect one another.
Therefore BE = DE, so that
2x² - x = x² + 6
x² - x - 6 = 0
Factorize.
(x + 2)(x - 3) = 0
x = -2, or x = 3.
When x = -2,
BE = 2(-2)² - (-2) = 10
DE = (-2)² + 6 = 10
Therefore BD = 20
When x = 3;
BE = 2(3²) - 3 = 15
DE = 3² + 6 = 15
Therefore BD = 30
Answer: Either 20 or 30.
BE = 2x² - x
DE = x² + 6
The intersecting diagonals bisect one another.
Therefore BE = DE, so that
2x² - x = x² + 6
x² - x - 6 = 0
Factorize.
(x + 2)(x - 3) = 0
x = -2, or x = 3.
When x = -2,
BE = 2(-2)² - (-2) = 10
DE = (-2)² + 6 = 10
Therefore BD = 20
When x = 3;
BE = 2(3²) - 3 = 15
DE = 3² + 6 = 15
Therefore BD = 30
Answer: Either 20 or 30.
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Answer:
6. x° is approximately 21.04°
7. x° is approximately 39.56°
8. x° is approximately 58.03°
9. x° is approximately 72.85°
Step-by-step explanation:
6. In the given right triangle (a triangle with the measure of one of the interior angles equal to 90°, indicated by the small square between two sides) , we have;
The hypotenuse side length = 15
The adjacent side to the given reference angle, x° = 14
By trigonometric ratio, we have;
To find the value of x°, we make use of the inverse cosine function, arccos found on a scientific calculator, as follows;
x° = arccos(14/15) ≈ 21.04°
x° ≈ 21.04°
7. In the given right triangle, we have;
The length of the opposite side to the given reference angle, x° = 19
The length of the adjacent side to the given reference angle, x° = 23
By trigonometric ratios, we have;
Therefore;
x° = arctan(19/23) ≈ 39.56°
x° ≈ 39.56°
8. In the given right triangle, the adjacent side to the reference angle, x° and the hypotenuse side are given, therefore, we have;
x° = arccos(9/17) ≈ 58.03°
x° ≈ 58.03°
9. The opposite side to the reference angle and the hypotenuse side are given
By trigonometric ratio, we have;
x° = arcsin(43/45) ≈ 72.85°
x° ≈ 72.85°.