5. The altitude of a right triangle is 7 cm less than its base. If the hypotenuse is 13 cm, find
the other two sides.
Answers
Answer:
The other two sides are 12 cm and 5 cm.
Step-by-step explanation:
Given :-
- The altitude of a right triangle is 7 cm less than its base.
- The hypotenuse is 13 cm.
To find :-
- Altitude and base of the right triangle.
Solution :-
Let the base of the right triangle be x cm.
★ The altitude of a right triangle is 7 cm less than its base.
Then,
- Altitude = (x-7) cm
Pythagoras Theorem :
→ (x-7)² + x² = 13²
→ x² - 14x + 49 + x² = 169
→ 2x² - 14x +49 -169 = 0
→ 2x² - 14x - 120=0
→ 2(x² - 7x - 60) = 0
→ x² - 7x -60 = 0
→ x² - (12-5)x - 60 = 0
→ x² - 12x + 5x -60 = 0
→ x(x-12) + 5(x-12) = 0
→ (x-12)(x+5) = 0
Either,
x - 12 = 0
→ x = 12
Or,
x+5 = 0
→ x = -5 [ impossible]
- Base of the right triangle = 12 cm
Then,
- Altitude = (12-7) = 5 cm
Answer:
Let base be x cm , then altitude will be (x-7) cm.
Now ,
By using pythagoras theorem-
132 = x2 + (x-7)2
169 = x2 + x2 + 49 - 14x
2x2 - 14x - 120 = 0
x2 - 7x - 60 = 0
x2 - 12x + 5x - 60 = 0
x ( x - 12 ) + 5 ( x - 12 ) = 0
Hence x = 12
sO , Altitude is 5 cm
AND. ,