Answer:
Question 1
This is a special triangle as the angles are 30-60-90
This means that the sides have a special ratio of
1 : √3 : 2 = short leg : long leg : hypotenuse
So the hypotenuse is twice the length of the short leg,
and the long leg is √3 times the length of the short leg.
Given:
- short leg = x
- long leg = y
- hypotenuse = 30
⇒ x = 30 ÷ 2 = 15
⇒ y = 15 × √3 = 15√3
Question 2
The sum of the interior angles of a triangle is 180°. Therefore the unknown angle of the triangle is 60°.
So again, this is a special 30-60-90 triangle, and we can use the same method as question 1 above.
Given:
- short leg = 5
- long leg = x
- hypotenuse = y
⇒ x = 5 × √3 = 5√3
⇒ y = 5 × 2 = 10
Question 3
Pythagoras' Theorem: a² + b² = c²
(where a and b are the legs, and c is the hypotenuse, of a right triangle)
To find x:
Given:
⇒ 8² + 6² = x²
⇒ x² = 100
⇒ x = √100
⇒ x = 10
To find y:
Given:
⇒ 5² + 10² = y²
⇒ y² = 125
⇒ y = √125
⇒ y = 5√5
Question 4
Pythagoras' Theorem: a² + b² = c²
(where a and b are the legs, and c is the hypotenuse, of a right triangle)
To find x:
Given:
⇒ 5² + 12² = x²
⇒ x² = 169
⇒ x = √169
⇒ x = 13
To find y:
Given:
⇒ y² + 13² = 14²
⇒ y² + 169 = 196
⇒ y² = 27
⇒ y = √27
⇒ y = 3√3