The scatter plot shows the number of text messages sent (x) and text messages received (y) by 10 students in a half hour. This is 25 points pls help

Choose the graph that matches the following system of equations: 7x + 2y = −6 6x − 7y = 21 a line includes points negative 2 comma 4 and 0 comma negative 3. a line includes points 6 comma 2 and 0 comma negative 3 a line includes points 0 comma negative 3 and 6 comma 2. a line includes points negative 2 comma 1 and negative 3 comma 4 a line includes points 0 comma negative 3 and negative 1 comma 4. a line includes points 0 comma negative 3 and negative 1 comma 3 a line includes points 0 comma 3 and negative 1 comma negative 3. a line includes points 0 comma negative 3 and negative 2 comma 4.

Express the following as a function of a single angle. cos(60) cos(-20) - sin(60) sin(-20)

Which describes the difference between the graph of f(x)=x^2 and g(x)=-(x^2-2)