The scientist must use 10 ounces of Solution A and 40 ounces of Solution B.
Step-by-step explanation:
Since a scientist has two solutions, which she has labeled Solution A and Solution B, each containing salt, and she knows that Solution A is 40% salt and Solution B is 90% salt, and she wants to obtain 50 ounces of a mixture that is 80% salt, to determine how many ounces of each solution should she use the following calculation must be performed:
100 x 0.9 + 0 x 0.4 = 90
90 x 0.9 + 10 x 0.4 = 85
80 x 0.9 + 20 x 0.4 = 80
50 x 0.8 = 40
Therefore, the scientist must use 10 ounces of Solution A and 40 ounces of Solution B.
I want to say -1. if you first combine like terms the equation would look like 2-2x. then next step i did was divide both sides by negative 2 to get the x by itself. after i did that i got -1 x.
