Set it up like this, going from words on the page to letters and variables:
-3(2x+5) = -57. Twice a number is 2x, increased by 5 is 2x+5, and that is multiplied by -3 to get a total of -57. Distribute the -3 into the parenthesis to get -6x - 15 = -57. Move the 15 over by addition to get -6x = -42. Divide both sides by -6 to get that x = 7
