How to solve the equation 2x + 7 / 0.3-2x-3 / 0.7 = 0.3

How to solve the equation 2x + 7 / 0.3-2x-3 / 0.7 = 0.3

2x+7/0.3-2x-3/0.7=0.3 10（2x+7）/3-10（2x-3）/7=0.3 70（2x+7）-30（2x-3）=6.3 140x+490-60x+90=6.3 80x=-573.7 x=-7.17125

2 ^ 2-2x + x ^ 2-19 = 0 solve the equation!
I did
2^2-2x+x^2=19
（2-x)^2=±19
2-x = ± 19 under root
-A1 = 19-2 under root
A1 = - 19 + 2 under root
A2 = 19-2 under root
The following a is replaced by X, wrong number.

Equal to (1-x) ^ 2 + 3 = 19
（1-x)^2=16
1-x==±4
A1 = negative 3 or A2 = 5, you need to move the item first. 1 ^ 2-2x + x ^ 2 is equal to (1-x) ^ 2