Question

The sides of a triangle are in the ratio 3:4:5 then the measure of the greatest angle is

• A. ${70}^{\circ }$
• B. ${80}^{\circ }$
• C. ${90}^{\circ }$
• D. ${100}^{\circ }$

Answer 1

The correct option is C ${90}^{\circ }$

The sides of a triangle are in the ratio 3:4:5

let the sides of triangle is 3x ,4x and 5x

As per Pythagorastheorem

$(5x{)}^2=(4x{)}^2+(3x{)}^2$

$\Rightarrow 25x^2=16x^2+9x^2$

$\Rightarrow 25x^2=25x^2$

So this triangle is right angle triangle

Then one angle ${90}^0$ and other angles total is ${90}^0$

Then greatest angle is ${90}^0$