Q+B=13. When B+3=0
You have 2 separate equations.
First solve the 2nd equation for B:
B +3 = 0
Subtract 3 from both sides:
B +3 - 3 = 0-3
Simplify:
B = -3
Now we have a value for B, we can replace b with -3 in the first equation and solve for Q:
Q + -3 = 13
Add 3 to each side:
Q + -3 + 3 = 13+3
Simplify:
Q = 16
So you have Q = 16 and B = -3
The concentration of solution would be the amount of the molecule divided by the volume. In this case, the solution concentration is 36% and the volume is 4 quarts + 1 quarts= 5 quarts. You are asked the concentration before 1 quarts added. The alcohol content should be same for both solutions. The answer should be:
concentration = alcohol content/ volume
alcohol content =concentration * volume
alcohol content1 =alcohol content2
36% * 5 quarts = concentration2 * 4quarts
concentration2= 36% * 5 quarts / 4 quarts= 45%
Slope intercept form is y = mx+b, so you can see that you set the equation equal to y. So if the equation is 2y+3x=6, then you solve for y to put it in slope intercept form.
2y + 3x = 6
2y = -3x + 6
y = (-3/2)x + 3
Keep in mind that the term with the x has to be before the constant, so it can't be y = 3 -(3/2)x
And by the way m is the slope and b is y-intercept, so in <span>y = (-3/2)x + 3, -3/2 is slope and (0,3) is y-intercept</span>
Let
x--------> <span>the speed of the boat in mph
we know that
</span>going upstream the speed is x-7
<span>going downstream the speed is x+7
</span>
let the distance be d
<span>time to go upstream = d/(x-7) </span>
<span>time to go downstream = d/(x+7)
</span>
time going upstream is 3 times going downstream
so
<span>3d/(x+7) = d/(x-7) </span>
<span>divide by d </span>
<span>3/(x+7) = 1/(x-7) </span>
<span>3x-21 = x+7 </span>
<span>2x = 28 </span>
<span>x = 14
</span>
the answer is
<span>the speed of the boat in still water is 14 mph</span>
