3 teas and 2 coffees have a total cost of £7.80 5 teas and 4 coffees have a total cost of £14.20 Work out the cost of one tea and the cost of one coffee.

You make simultaneous equations. 1.) 3T+2C=7.82.) 5T+4C=14.2Then you make either the C or the T coefficient equal in both equations. I choose to make the C coefficients the same. So I multiplied equation 1 by 2. This meant that the new equations are now:1.) 6T+4C=15.62.) 5T+4C=14.2So now we subtract equation 2.) from 1.):T=1.4Now we have T we can sub T in to get C. So we now have the following equation:
3(1.4)+2C=7.8
Now we solve for C:
4.2+2C=7.8
2C=3.6
c=1.8