Question

solve question no. 13....

Answer 1

$let \: base \: angla \: b= {x}^{.} \\ \\ \: \: \: \: \: \: angle \: c = {x}^{.} (because \: isoscelus \: triangle) \\ \\ then.vertex \: angle \: a = 180 - (x + x) \\ \\ but \: \\ according \: to \: question \\ \\ = > 180 - (x + x) = 2(x + x) \\ = > 180 - 2x = 2 \times 2x \\ = > 180 - 2x = 4x \\ = > 180 = 4x + 2x \\ = > 180 = 6x \\ = > x = \frac{180}{6} \\ = > x = 30 \\ \\ \\ hence \: angle \: b = 30 \\ angle \: c = 30 \: and \: angle \: c = 180 - 60 = 120 \\ \\ so \: angles \: are \: 30 \: 30 \: and \: 120$
I hope this helps you....