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What is the value of X when a triangle has sides of 15cm by Xcm by X-3cm which is opposite to an angle of 60 degrees?
Wiki User
∙ 6y ago
The cosine rules for a triangle ABC with sides a (opposite angle A), b (opposite angle B) and c (opposite angle C) states:
a² = b² + c² - 2bc cos A
Here:
A = 60°
a = X - 3 cm
b = 15 cm
c = X cm
(the assignment of b and c doesn't matter as they can be interchanged in the rule)
→ (X - 3)² = 15² + X² - 2 × 15 × X × cos 60°
→ X² - 6X + 9 = 225 + X² - 15X × 2 × ½
→ -6X + 9 = 225 -15X
→ 9X = 216
→ X = 24
Wiki User
∙ 6y ago
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What is the largest angle of a triangle with sides of 14 cm 8.5 cm and 9 cm?
The largest angle of the triangle will be opposite its largest side and by using the Cosine Rule it works out as 106.23 degrees.
What is the smallest angle of a triangle with sides of 6.4 cm 8.2 cm and 5.7 cm?
The smallest angle will be opposite the smallest side of the triangle and so by using the cosine rule it works out as 43.84 degrees.
What is a triangle that has two equal sides and the angle opposite the equal sides are also equal?
an isosceles triangle
What is a polygon with no pairs of opposite sides parallel at most 2 acute angles and a total angle measure of 200 degrees?
triangle
What can you say about the sides of a triangle opposite the largest angle?
The side of a triangle opposite the largest angle is the side of greatest length. It is also known as the Hypotenuse.
What is the largest angle of a triangle with sides of 14 cm 8.5 cm and 9 cm?
The largest angle of the triangle will be opposite its largest side and by using the Cosine Rule it works out as 106.23 degrees.
What are the sides of a triangle called?
Given the reference perspective of a specific angle the sides are are the adjacent sides and the opposite side If we have a right triangle the longest side (opposite the right angle) is the hypotenuse.
A triangle with two congruent sides and an angle of 104 degrees is?
A triangle with two congruent sides is isosceles. A triangle with an angle of 104 degrees is obtuse. So you would have an obtuse isosceles triangle.
If two sides in a triangle are congruent then their opposite angles are?
Their opposite angle are equal and all 3 angles will add up to 180 degrees
How do you find the angle opposite of the hypotenuse of a triangle with all three sides known?
The only triangle that has a hypotenuse is a right-triangle. The hypotenuse is the side opposite the right angle, so the angle is always 90 degrees. In this case, if you're just finding the angle then you don't need to know what the side lengths are.
What is a triangle that has two equal sides and the angle opposite the equal sides are also equal?
an isosceles triangle
What is the smallest angle of a triangle with sides of 6.4 cm 8.2 cm and 5.7 cm?
The smallest angle will be opposite the smallest side of the triangle and so by using the cosine rule it works out as 43.84 degrees.
Can a right triangle have three acute angles and three equal sides?
No, a right angled triangle cannot have three acute angles because an acute angle is less than 90 degrees and a right angled triangle has one angle of exactly 90 degrees (which is what right angled means, equal to 90 degrees).Also, because the triangle has a right angle (of 90 degrees) it cannot have three equal sides; it can have two equal sides but the side opposite to the right angle (the hypotenuse) will always be longer than either of the other two sides.
What is a polygon with no pairs of opposite sides parallel at most 2 acute angles and a total angle measure of 200 degrees?
triangle
What is a triangle with an angle of 110 degrees and two congruent sides?
a scalene triangle
What can you say about the sides of a triangle opposite the largest angle?
The side of a triangle opposite the largest angle is the side of greatest length. It is also known as the Hypotenuse.
What is the name for the sides of a right triangle that are adjacent to the right angle?
Opposite and adjacent sides.
