Respuesta :

Answer:

∠a=44,∠b=47, ∠c=89

Step-by-step explanation:

we can note that

∠a+∠b+∠c=180

hence,

3x+5+5x-18+7x-2=180

therefore,

3x+5x+7x+5-18-2=180

15x-15=180

15x=180+15

15x=195

x=[tex]\frac{195}{15}[/tex]

then, x=13.

with this values we can find all the angles:

∠a=3x+5 ⇒∠a=3(13)+5⇒∠a=39+5⇒∠a=44

∠b=5x-18⇒∠b=5(13)-18⇒∠b=65-18⇒∠b=47

∠c=7x-2⇒∠c=7(13)-2⇒91-2⇒∠c=89

We can corroborate these result by adding them.

∠a+∠b+∠c=

44+47+89=180

Thats right !!