Q7. The perimeter of a triangle is 240cm. If two of its sides are 78cm and 50cm. Find the length of
perpendicular corresponding to the smallest side
Answers
I hope my answer is correct
Given : The perimeter of a triangle is 240 cm. two of its sides are 78 cm and 50 cm.
To find : the length of perpendicular corresponding to the smallest side.
solution : perimeter = sum of all sides
⇒240 cm = 78cm + 50cm + 3rd side
⇒240 - 128 = 3rd side
⇒3rd side = 112 cm
therefore smallest side is 50cm.
now we have find length perpendicular drawn to smallest side ( i.e., 50 cm)
if ABC is triangle where AB = 78cm, BC = 50cm and AC = 112 cm. one altitude is drawn from A to BC as shown in figure. hence AT is altitude
so area of Triangle ABC = 1/2 × BC × AT
⇒√{s(s - a)(s - b)(s- c)} = 1/2 × 50 × AT
⇒√{120(120 - 78)(120 - 50)(120 - 112)} = 25 × AT
⇒√{120 × 42 × 70 × 8} = 25 × AT
⇒1680/25 = AT
⇒AT = 67.2 cm
Therefore the length of perpendicular to the smallest side is 67.2 cm