Solve the system using substitution. Show all work

Answer:x = -2 , y = 3Step-by-step explanation:Solve the following system: {4 x + 5 y = 7 y = 3 x + 9 Hint: | Perform a substitution. Substitute y = 3 x + 9 into the first equation: {4 x + 5 (3 x + 9) = 7 y = 3 x + 9 Hint: | Expand the left hand side of the equation 4 x + 5 (3 x + 9) = 7. 4 x + 5 (3 x + 9) = (15 x + 45) + 4 x = 19 x + 45: {19 x + 45 = 7 y = 3 x + 9 Hint: | Choose an equation and a variable to solve for. In the first equation, look to solve for x: {19 x + 45 = 7 y = 3 x + 9 Hint: | Isolate terms with x to the left hand side. Subtract 45 from both sides: {19 x = -38 y = 3 x + 9 Hint: | Solve for x. Divide both sides by 19: {x = -2 y = 3 x + 9 Hint: | Perform a back substitution. Substitute x = -2 into the second equation: Answer:  {x = -2 , y = 3