Answer:It
It can be 12, 13, 14 and more up
Step-by-step explanation:
Is that because 12+7= 19 which is bigger than 18
Option A is true because the sum of angles in a triangle is 180, so we can rule that one out immediately.
We can solve for x for the other 3 options by setting up this equation:
7x+2 + 4x+7 + 8x = 180 | Simplify
19x + 9 = 180 | Subtract 9
19x = 171 | Divide by 19
x=9
Now we can substitute x into all the values:
<J = 7x+2 = 65
<L = 4x+7 = 43
<K = 8x = 72
Looking at the options again, we can see that A, B, and D are true, leaving C to be false.
Answer:
7)141
8)65
Step-by-step explanation:
<span>Dr. Graham currently has two acid solutions.
60% acid AND 20% acid </span>
Dr. Graham needs 30 L of a 50% acid solution
We set up 2 equations in which s = 60% acid and t = 20% acid
A) s + t = 30
B) .60s + .20t = (.50 * 30)
We multiply equation A by -.20
A) = -.20s -.20t = -6 then we add it to B)
B) .60s + .20t = 15
.40s = 9
s = 22.5
t = 7.5
So, she needs to mix 22.5 liters of 60% acid with 7.5 liters of 20% acid.
Source:
http://1728.org/mixture.htm