Please answer I will mark brainliest for best answer ^>^

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.

The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)