When using substitution, you want to solve an equation for one variable that doesn’t make the equation worse to work with.
The general idea is that you want to find a variable that has a coefficient of 1 or -1.
In 2.5x - 7y = 7.5, both variables have “bad” coefficients.
In 6.2x - y = 1, the y has a coefficient of -1. That’s where you want to start.
<span>Let x denote number of ounces of 30-cent iodine.
Mixing of 50 ounces of 18-cent iodine and x ounces of 30-cent iodine will result in (50+x) mixture of iodine. We want the mixture to be worth 20 cent per ounce.
The value of 50 ounces of 18-cent iodine is of course
50â‹…18=900.
Similarly, x ounces of 30-cent iodine is worth 30â‹…x.
Finally, 50+x ounces of 20-cent iodine will cost (50+x)â‹…20.
30x+50â‹…18=(50+x)â‹…20
30x+900=1000+20x
10x=100
x=10</span>
10.
50+(2x)=20+(5x)
-20 -20
-2x -2x
30=3x
divide both sides by 3
10=x
Answer:
3×d+5b×3
=3d+15b.
I think it will help you.
Answer:
b
Step-by-step explanation:
