Question

A triangular bandana has an area of 78 square inches. The height of the triangle is 9

Answer 1

Area of a triangle = 1/2 × base × height

Plug in what we know.

78 = 1/2 × b × 9¾

Multilply each side by 2 to get rid of the 1/2...

156 = b × 9¾

Write 9¾ as an improper fraction.
(9¾ = 9 + 3/4 = (9×4)/4 + 3/4 = 36/4 + 3/4 = 39/4)

156 = b × 39/4

Multiply each side by 4...

624 = b × 39

Divide each side by 39...

16 = b

Done! The length of the base of the triangle is 16 inches.