How many solutions can be found for the system of linear equations represented on the graph?

The line y = x + passes through (−3, 7) and is parallel to y = 4x − 1.

The anwser cause i do not understand just plez

Given the quadratic function f(x)=3x^2-24x+49 a. use “completing the squares” to convert the quadratic function into vertex form b. state the vertex c. find the x and y intercepts d. graph the function