1..The distributive property is when you take the number and multiply it to the numbers in the parentheses
2.You must use the distributive property because it helps simplify difficult problems and breaks the problem down into a simpler version
3. To solve a multi step equations with parentheses you must use the addition property subtraction property distributive property in multiplication property if all are needed
Answer:
15.
16. 10 ml of 20% saline and 40 ml of 10% saline
Step-by-step explanation:
A chemist takes x ml of 20% saline and y ml of 10% saline. In total, he takes
x + y ml that is 50 ml, so
There are 
ml of salt in x ml of 20% saline and 
ml of salt in 10% saline. There are 
ml of salt in 50 ml of 12% saline. Thus,
15. We get the system of two equations:
16. Solve this system. From the first equation:
Substitute it into the second equation:
Answer:
a = -15, b = -.5, c = -1
Step-by-step explanation:
1/3a = -5 --> multiply each side with 3 --> a = -15
12 - b = 12.5 --> subtract 12 from both sides --> -b = .5 --> multiply each side with -1 to get b positive --> b = -.5
.1 = -10c --> multiply each side with -10 --> c = -1
