SOLUTION: Through(3,4) perpendicular to y =-3x+2 Dmitri needs 5 liters of a 43% solution of sulfuric acid for a research project in molecular biology. He has two supplies of sulfuric a

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Question 362017: Through(3,4) perpendicular to y =-3x+2

Dmitri needs 5 liters of a 43% solution of sulfuric acid for a research project in molecular biology. He has two supplies of sulfuric acid solution: one is an unlimited supply of the 40% solution and the other an unlimited supply of the 45% solution. How many liters of each solution should Dmitri use?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

Through(3,4) perpendicular to y =-3x+2 

y = (1/3)x + b  Slopes of perpendicular lines are negative reciprocals

(3,4)

4 = 1 + b    substituting the ordered pair to solve for b

3 = b

y = (1/3)x + 3



2nd question

Let x represent the 45% solution, then (5-x) would represent the 40% solution

.40(5-x) + .45x = .43*5L

solving for x

.05x = .43*5 - .40*5L

.05x = .03*5 = .15L

x = 3 L of 45% solution and (5-3) or 2L of 40% solution

checking our answer

.40*2 + .45*3 = .08 + 1.35 = 2.15