The height of a triangle is 5 m less than its base. The area of the triangle is 42 m². Find the length of the base. 7m 8 m 11 m 12 m

Question

asked Dec 2, 2020 156k views

2 Answers

Zudov · Answer 1 · 2020-12-09T11:41:58+0000

Answer:

12 m

Explanation:

Area of a triangle is:

A = ½ bh

Given that h = b - 5 and A = 42:

42 = ½ b (b - 5)

84 = b² - 5b

0 = b² - 5b - 84

0 = (b + 7) (b - 12)

b = -7, 12

The length of the base can't be negative, so b = 12 m.