Can someone help me with this math homework please!

3x = 729 solve for x plz . it's urgent. will mark

Solve the system of equations using the linear combination method. {4x−3y=127x−3y=3 enter your answers in the boxes.

Which of these statements is correct? the system of linear equations 6x - 5y = 8 and 12x - 10y = 16 has no solution. the system of linear equations 7x + 2y = 6 and 14x + 4y = 16 has an infinite number of solutions. the system of linear equations 8x - 3y = 10 and 16x - 6y = 22 has no solution. the system of linear equations 9x + 6y = 14 and 18x + 12y = 26 has an infinite number of solutions.