Question

Find the value of n.

Answer 1

20cm

Explanation:

Answer 2

n = 15

Explanation:

The area (A) of a triangle is calculated as

A =
`(1)/(2)` bh ( b is the base and h the height )

Here b = n + 1 and h = n + 1 - 5 = n - 4 , then

`(1)/(2)`(n + 1)(n - 4) = 88 ( multiply both sides by 2 to clear the fraction )

(n + 1)(n - 4) = 176 ← expand the left side using FOIL

n² - 3n - 4 = 176 ( subtract 176 from both sides )

n² - 3n - 180 = 0 ← in standard form

(n - 15)(n + 12) = 0 ← in factored form

Equate each factor to zero and solve for n

n - 15 = 0 ⇒ n = 15

n + 12 = 0 ⇒ n = - 12

However, n > 0 , thus value of n = 15