00:01
All right, guys.
00:01
So for this problem, we're going to let x represent the amount of 8 % of hydrogen chloride and y is going to represent the amount of 15 % of hydrogen chloride that we have.
00:14
So we know that in the lab, we're trying to make 37 millimeters of 12 % hydrogen chloride solution.
00:23
So we can represent as saying x plus y is equal to 37.
00:29
Now, in the actual lab, we only have the 8 % and the 15 % amount of hydrogen and chloride.
00:36
So we're trying to figure out how many milliliters of each will we need to make our solution.
00:43
So we can say 0 .08 because we're writing 8 % in decimal form of x amount of solution plus 0 .15 of y amount of solution will give us the 37 milliliters.
00:59
Of 12 % of the hydrogen chloride.
01:02
So that's where we get our two equations from.
01:06
Now, we can rewrite our first equation by saying y is equal to negative x plus 37.
01:13
And we can use that to substitute back into our second equation in place for y...