Can someone explain to me step by step how to do
5/13x=-9

Can someone me with my math problems i have a bunch. i will give brainliest and lots of pleeeaaasssee

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

How many liters of peroxide should be added to 12 liters of an 8% peroxide solution so that the resulting solution contains 16% peroxide?   original added new amount of peroxide 0.96 liters x 0.96 + x amount of solution 12 liters x 12 + x 0.18 liter 1.14 liters 1.92 liters 2.10 liters