Well first you have fallow the pemdas rules this means you have to solve your eeequation in order from parenthesis, exponents, multiplication, division, addition, and last subtraction... So first you have to do distributive property with you -4 and teh parenthesis this gives you 8k-4k+1+7-k now you have to add or subtract you common like terms( common like terms are terms that have the same thing for example 8k,-4k, and k are coomon like terms and 1 and 7 are coomon like terms) when you add them you will eb able to get your final answer.... Your answer should be "3k+8"\
Now if you wnat to solve for k you have to set every number aside to leave the k by itself. First subtract the 8 to the right side (you do this because 8 is a positive and the only way to get rid of a positive is with a negative) so now you should be left with 3k=-8 now our final step to leave k by itself is divide 3 in both sides( you do this because the only way to get rid of a multiplication is dividng) now you shoudl be left with K=-8/3. Good job!!!! we found our last result. this means that after everything we did your answer should be K=-8/3
extraneous root is a solution o an equation that seems to be right but when we check it (by substituting it into the original equation) it turns out not to be right