In Franconia it cost Henry 150 cents to send 1 postcard and 1 letter home. His wife, Isobel, sends 5 postcards and 1 letter witch, in total, costs her 390 cents. Form the two equations in words and symbols.

So I'm guessing that the unknowns here would be the number of postcards and letters that the couple sends to each other. So let's represent a letter with L and a postcard with the letter P. To get the equation of henry and isobel, you just need to plot the variables and the numbers. So the equation of henry is L + P = 150 because he only sent one letter and one postcard that made a total of 150. Isobel's equation is 5P + L = 390 because isobel sent five postcards hence 5P, and one letter to make a total cost of 390.