How would you go about solving this?

Plot the points (0,6), (3,15.8), and (9.5,0) using the graphing tool, and find the function

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

Solve this equation using substitution. {4x + y = −2} {4x + 6y = 44}