What is the x-coordinate at the point of intersection for these equations? f(x) = 2.8x - 12 g(x) = 5.8x + 9

For this case we have the following equations:
 f (x) = 2.8x - 12
 g (x) = 5.8x + 9
 We must equalize the equations.
 We have then:
 f (x) = g (x)
 2.8x - 12 = 5.8x + 9
 We clear x:
 x (5.8-2.8) = -12 - 9
 3x = - 21
 x = -21 / 3
 x = -7
 
 The x-coordinate at the point of intersection for these equations is:
 x = -7