18/12=1.5 dozens 1 dozens= 12
Step-by-step explanation:
a. we simply subtract 3. from 2.
x + 2y + z = 15
- -3x + y + z = 2
--------------------------
4x + y 0 = 13
b. we multiply 3. by 3 and then subtract from 1.
2x - 4y + 3z = -7
- -9x + 3y + 3z = 6
-----------------------------
11x - 7y 0 = -13
c. we multiply the result of a. by 7, and then simply add a. and b., because the y terms have different signs already.
28x + 7y = 91
+ 11x - 7y = -13
--------------------------
39x 0 = 78
39x = 78
x = 2
d. we use this x = 2 in the result of a.
4×2 + y = 13
8 + y = 13
y = 5
e. using x = 2 and y = 5 in 2.
2 + 2×5 + z = 15
2 + 10 + z = 15
12 + z = 15
z = 3
the solution is therefore (2, 5, 3).
Answer:
The solution is 
.
Step-by-step explanation:
The best way to solve this exponential equation is applying the logarithm of base 10 to each side of the equality.
It is also important to remember the following logarithm proprierty:
So
The solution is .
The value of 9−(−12) as an addition expression is 3.
<h3>What is a expression?</h3>
Expression simply refers to the mathematical statements which have at least two terms which are related by an operator and contain either numbers, variables, or both. Addition, subtraction, multiplication, and division are all possible mathematical operations.
In this case, the expression given is illustrated as:
-9 - (-12)
It's important to note that (-) × (-) = +
Therefore, -9 - (-12)
= - 9 + 12
= 3
Learn more about expressions on:
brainly.com/question/723406
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