Answer:

Step-by-step explanation:
In this question, you are combining like terms, meaning doing equations to numbers that fit with only each other.
<u>So we should start on the number without variables:</u>
23 and 27
<u>Match them up together and you should find your first equation:</u>
23 - 7
==> -4
So we should have -4 + 8m + 4n - 5m
Now we should combine the numbers with the variable of m:
8m and 5m
<u>Match them up together and you should find your first equation:</u>
<u></u>
8m - 5m
==> 3m
So we should now have -4 + 3m + 4n
<u></u>
<u>Since there are no other variables of n, we are all done:</u>
<u>-4 + 3m + 4n is your final answer </u>
Solving a system of equations we will see that we need to use <u>40 liters of the 80% acid solution</u>, and the other <u>20 liters are of the 35% acid solution</u>.
<h3>
How many liters of each solution do we need to use?</h3>
First, we need to define the variables:
- x = liters of the 35% acid used.
- y = liters of the 80% acid used.
We know that we want to produce 60 liters of 65% acid, then we have the system of equations:
x + y = 60
x*0.35 + y*0.80 = 60*0.65
(in the second equation we wrote the percentages in decimal form).
To solve this we need to isolate one of the variables in one equation and then replace it in other one, isolating x we get:
x = 60 - y
Replacing that in the other equation:
(60 - y)*0.35 + y*0.80 = 60*0.65
y*(0.80 - 0.35) = 60*(0.65 - 0.35)
y*0.45 = 60*0.30
y = 60*0.30/0.45 = 40
So we need to use <u>40 liters of the 80% acid solution</u>, and the other <u>20 liters are of the 35% acid solution</u>.
If you want to learn more about systems of equations:
brainly.com/question/13729904
#SPJ1
Step-by-step explanation:
I guess the answer is 187MB
The entire picture is needed to solve. the bottom of the pic is cut off