The system of equations "a+b=7" and "ab=9" should be solved directly in either Algebrator, doyourmath.com or quickmath.com. The values for 'a' and 'b' can then be used to solve for "a^2 + b^2".

Free trial versions of Algebrator are available through these links:

Windows: https://www.softmath.com/tr/alg51win-tr-en.exe

Mac: https://www.softmath.com/tr/alg51mac-tr-en.dmg