Solve the system of equations using substitution or elimination by addition. 3x + 9y = - 6 4x + 6y = - B Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. The solution is (Type an ordered pair.) O B. There are infinitely many solutions. O c. There is no solution.Solve by using substitution or elimination by addition. 3x - 2y = 1 - 6x + 4y = - 2 Select the correct choice below and fill in any answer boxes present in your choice. O A. The unique solution to the system is (Type an ordered pair.) O B. There are infinitely many solutions. O C. There is no solution.Graph the equations below in the same coordinate system. Find the coordinates of any points where two or more lines intersect and discuss the nature of the solution set. x - 2y= - 6 2x+ y= B x + 2y = - 14 X Use the graphing tool to graph the system. Click to enlarge graphSuppose that the supply:' and demand equations for printed Tshirts for a particular week are given as follows. where p is the prioe in dollars and q is the quantity in hundreds. p = (3.5:; + 4 Price-suppiyequaon p = -1.3q + 13 Price-demand equation Answer parts {A} through (D) below. {A} Find the supply and demand {to the nearest unit) if T-shirts are $5 each. To use the price-supply and pricedemand equations to nd the requested mantities, substitute $6 for E The number of units supplied or demanded will be given by El