Question Video: Changing the Subject of an Exponential Equation Mathematics • Second Year of Secondary School

Video Transcript

Make 𝑥 the subject of the equation 𝑦 equals two to the 𝑎𝑥 plus 𝑏 power, assuming that 𝑎 does not equal zero.

We can go from exponential form to logarithmic form, 𝑎 to the 𝑥 power equals 𝑏. So taking our equation and using the same circle method, two to the 𝑎𝑥 plus 𝑏 equals 𝑦. Now let’s solve for 𝑥. Let’s subtract 𝑏 and then divide by 𝑎. So we’ve subtracted 𝑏 and now divide both sides by 𝑎.

Therefore, log base two of 𝑦 minus 𝑏 divided by 𝑎 is equal to 𝑥.