$2.7x+3.4y=-82$ is in standard form, with $A=2.7\text{,}$ $B=3.4\text{,}$ and $C=-82\text{.}$ $y=\frac{2}{7}(x-3)+\frac{1}{10}$ is in point-slope form, with slope $\frac{2}{7}\text{,}$ and passing through $\left(3,\frac{1}{10}\right)\text{.}$ $12x-3=y+2$ is linear, but not in any of the forms we have studied. Using algebra, you can rearrange it to read $y=12x-5\text{.}$ $y=x^2+5$ is not linear. The exponent on $x$ is a dead giveaway. $x-y=10$ is in standard form, with $A=1\text{,}$ $B=-1\text{,}$ and $C=10\text{.}$ $y=4x+1$ is in slope-intercept form, with slope $4$ and $y$-intercept at $(0,1)\text{.}$