The sum of a number and 9 is multiplied by -2 and the answer is 8 find the number. i know the answer is -5 i need a expression, or equation. any of them both

Technicians have installed a center pivot, circular irrigator for a farm that covers 25 acres. a.) how long is the irrigation boom (in feet) from the center pivot to its farthest extent? b.) if the irrigation boom makes 4 full revolutions in a day, how many miles does the end of the boom travel in 5 days?

:i need some real : a store sells shirts to the public at one pricing scale and wholesale at another pricing scale. the tables below describe the cost, y, of x shirts. (after tables) how do the slopes of the lines created by each table compare? the slope of the public table is 3/4 of the slope of the wholesale table.the slope of the wholesale table is 3/4 of the slope of the public table.the slope of the public table is 12 times greater than the slope of the wholesale table.the slope of the wholesale table is 12 times greater than the slope of the public table.

Isabelle is mixing red and blue paint to make purple paint she adds 3/10 of a fluid ounce of red to 12/25 of a fluid ounce of blue to make 1 1/30 fluid ounces of purple how many fluid ounces of red paint ounces of red paint will she need to make 3 fluid ounces of purple paint