42nd B.P.S.C. (Pre) 1997-98

If the sides of a triangle are 11m, 60m and 61m, then choose the height of triangle relative to longer side.

a10 m
b9 m
c10.8 m✓ Correct
d9.8 m

Explanation

It is clear that given triangle is right angled triangle $\Delta$ because $(11)^2 + (60)^2 = (61)^2$ Area of triangle = $\frac{1}{2} \times 60 \times 11 = 330$ sq. m. ($\therefore$ Area of right angle triangle = $\frac{1}{2} \times base \times height$) Let height on hypotenuse = $h$ Now, let the hypotenuse as base and perpendicular as base then, Area of triangle = area of $\Delta$ABC $330 = \frac{1}{2} \times h \times 61$ $h = 10.81$ m So, height = 10.81 m

general-science