Question

Two angles of a triangle are equal and the third angle is greater than each one of them by 18°.find the angles.

Answer 1

∠1 = ∠2  

∠3 = ∠2+18 = ∠1 + 18

so,

∠1+∠2+∠3 = 180

∴ 2∠1 + ∠1 + 18 = 180

or, 3∠1 = 162

or, ∠1 =54

∴ ∠1 =54 ; ∠2 = 54 ; ∠3 = 72

Answer 2

sum of all angles in a triangle=180
so
$x + x + (x + 18) = 180$
$3x + 18 = 180$
$3x = 180 - 18 = 162$
$x = x = 162 \div 3$
$x = 54$
first angle =second angle=54
third angle=54+18=72