danemathesius

first you multiply the 3-7 over to the other side, and then distribute, so you have p=-6+14, which reduces to p=8.

except if there is an amplitude change

because sine is never greater than one. 

$${\mathtt{8}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{6}}{\mathtt{\,\times\,}}{\mathtt{x}} = {\mathtt{2}}{\mathtt{\,\times\,}}{\mathtt{x}}$$         

$${\mathtt{\,-\,}}{\mathtt{19}}{\mathtt{\,\small\textbf+\,}}{\mathtt{3}} = -{\mathtt{16}}$$

$${\mathtt{\,-\,}}{\frac{{\mathtt{16}}}{{\mathtt{2}}}} = {\mathtt{x}}$$

$${\mathtt{x}} = -{\mathtt{8}}$$