Question

[(3xa+4)x2+5]x3+5=170

Answer 1

[(3a+4)×2+5]×3=170-5
[(3a+4)×2+5]×3=165
[(3a+4)×2+5]=165:3
[(3a+4)×2+5]=55
(3a+4)×2=55-5
(3a+4)×2=50
3a+4=50:2
3a+4=25
3a=25-4
3a=21
a=21:3
a=7

Answer 2

[(3xa +4) x2 +5] x3 +5=170

[(3 x a+4) x 2  + 5] x 3 =170-5

[( 3 x a+4 ) x 2 +5 ] x 3=165

[( 3 x a+4 ) x 2 +5 ] =165:3

( 3 x a +4) x 2 + 5 =55

(3 x a + 4 ) x 2 =55-5

(3 x a + 4 ) x 2 = 50

3 x a + 4 =50:2
3 x a + 4 =25
3 x a =25- 4
3 x a=21
a= 21 :3

a =7