the sides of a triangle are xcm,x+3cm and 10cm.if x is a whole number of cm,find the lowest value of x

Answer 1

well, you must have
(x+3)-x < 10 < (x+3)+x
3 < 10 < 2x+3
since 3 < 10, that's the same as
2x+3 > 10
2x > 7
x > 3.5
So, x must be at least 4.

check: Sides of 4,7,10 form a triangle
3,6,10 do not, since even if the 3,6 sides are laid flat on top of the 10 side, they are not long enough to cover it.