Answer:
The solutions are:
Step-by-step explanation:
We have the following quadratic equation
We can rewrite the equation as follows
Now we use the quadratic formula to solve the equation
For an equation of the form 
the quadratic formula is:
In this case:
Then:
X+x^2=2
x^2+x-2=0
(x+2)(x-1)=0
So x=-2, 1
To answer this multiply 3×7=21 and add 21+10=31. so it is 31/10 divided by 2. for that you do this...( top pic)
In five quarts, we have 2 quarts of acid and 3 quarts of water
total = (2 + 3) = 5 quarts
concentration = 2 / 5
We want a 30% concentration
total volume = 2 + x
.30 = 2 / (2+x)
.6 + .30 x = 2
.30x = 1.4
x = 4.66666 gallons of water
(or we need to add 1.666666 gallons of water)
Double Check:
acid concentration = 2 / (2 + 4.666666)
acid concentration = .30
