I am reviewing this to teach this concept this year, and I have completely forgotten how to do these questions. Am I right in the fact that it needs to be some combination of multiplication, division and indices to reach 98 using 5 and 2? My instinct was 5*2*5*2-2 but that doesn't tie in with the log laws. This is frustrating me! Help!
$\log_7 98 = \log_7 (7^2 \times 2) = \log_7 (7^2) + \log_7 2 \approx 2.36$
$\log_7 70 = \log_7 (7 \times 5 \times 2) = \log_7 7 + \log_7 5 + \log_7 2 \approx 1 + .83 + .36 = 2.19$