Question

(-3)k+1×(-3)cube=(-3)7 what is the value of k​

Answer 1

Answer:

${( - 3)}^{k + 1} \times {( - 3)}^{3} = {( - 3)}^{7} \\ {( - 3)}^{k + 1} = \frac{ {( - 3)}^{7} }{ {( - 3)}^{3} } \\ {( - 3)}^{k + 1} = {( - 3)}^{7 - 3} \\ {( - 3)}^{k + 1} = {( - 3)}^{4} \\ k + 1 = 4 \\ k = 4 - 1 \\ \large k = \underline{ \underline{ \bf 3}} \\ \\ \large \underline {Note}: \\ * \: \: \: {a}^{m} \div {a}^{n} = {(a)}^{m - n} \\ * \: \: \: If \: \: {a}^{m} = {a}^{n} , \: \: then \: \: m = n$