f(x) = mx + b
m = slope = -5
f(2) = 10 = (-5)(2) + b
b = 10 + 10 = 20
Ans. m=-5, b = 20
A.) wooden blue, wooden green.....
19 is the answer because you just divided 228 by 12
Let t, f, and s be the amount of 25%, 40%, and 60% solutions used.
We are told s=3f. The general equation is:
100(0.25t+0.4f+0.6s)/(t+s+f)=45, and using s=3f we have:
(0.25t+0.4f+1.8f)/(t+4f)=0.45
(0.25t+2.2f)/(t+4f)=0.45
0.25t+2.2f=0.45t+1.8f
0.25t+0.4f=0.45t
0.4f=0.2t
t=2f, remembering that s=3f, will allow us to solve for f
t+s+f=60, using t and s from above
2f+3f+f=60
6f=60
f=10 L then
s=3f=30 L and t=2f=20L
So 20L of 25%, 10L of 40%, and 30L of 60% acid solutions need to be mixed to make 60L of 45% acid solution.
