CPhill

(3 + 5/9)  + (2 + 3/5) =

32/9   +   13/5     

[5*32  + 9*13]  / [ 9*5]  =

[160 + 117] / 45  =

277 / 45   = 6 + 7/45

20 + g + g  = 4

20 + 2g = 4    subtract 20 from both sides

2g = -16     divide both sides by 2

g = -8

About 53.1°

31 +  (-6)  =  25

Rearrange as

a/a x b/b x c/c  =

1 x 1 x 1  =

1  [ assuming, a, b, c   not equal to 0 ]

(-2/3)³  =  

(-2)³ / (3)³  =

-8 / 27

15t-2(3-4t)+6(t-1)  =

15t - 6 + 8t + 6t - 6  =   combine like terms

29t - 12

2sqrt(7)  + sqrt(7)  = 3sqrt(7)

This is analogous to having

2x +  x = 3x

5 x 10⁰      

4x < 8    divide both sides by 4

x < 2