Question

3a +7b upon 3a-7b =4 upon 3
then find the value of ratio
3a square - 7b square upon
3a square + 7b square​

Answer 1

$(3a + 7b) \div (3a - 7b) = 4 \div 3 \\ by \: alternando \: \\ (3a - 7b) \div( 3a - 7b) = 3 \div 4 \\ squaring \: both \: sides \: \\ {((3a - 7b) \div (3a + 7b)}^{2} = {3}^{2} \div {4}^{2} = 9 + 16 = 25$

hope it's correct