Teddy wants to know the value of \(x\) in \(49 + x = 56\) . He knows the difference of \(56\) and \(49\) is \(7\) . How can he find the value of \(x\) ? Explain.
Teresa wants to find the difference of \(136\) and \(117\) . She knows the sum of \(117\) and \(19\) is \(136\) . How can she find the difference? Explain.