Answer:
(3, -9)
General Formulas and Concepts:
<u>Pre-Algebra</u>
- Order of Operations: BPEMDAS
- Equality Properties
<u>Algebra I</u>
- Solving systems of equations using substitution/elimination
- Solving systems of equations by graphing
Step-by-step explanation:
<u>Step 1: Define systems</u>
-5x - 3y = 12
y = x - 12
<u>Step 2: Solve for </u><em><u>x</u></em>
<em>Substitution</em>
- Substitute in <em>y</em>: -5x - 3(x - 12) = 12
- Distribute -3: -5x - 3x + 36 = 12
- Combine like terms: -8x + 36 = 12
- Isolate <em>x</em> term: -8x = -24
- Isolate <em>x</em>: x = 3
<u>Step 3: Solve for </u><em><u>y</u></em>
- Define original equation: y = x - 12
- Substitute in <em>x</em>: y = 3 - 12
- Subtract: y = -9
<u>Step 4: Graph systems</u>
<em>Check the solution set.</em>
Answer:
4,8
Step-by-step explanation:
let the numbers be x and y
x+y=12
x-y=-4
add
2x=12-4=8
x=8/2=4
4+y=12
y=12-4=8
so numbers are 4 and 8
Answer:
22
Step-by-step explanation:
We are given the expression:—

When n = 5, substitute/change n to 5:—

Evaluate:—

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<u>Summary</u>
<u>Substitution</u>
Changing or replacing from a term to another terms/expression is called substitution.
Examples:—
If we are given the expression
and we want to find the value when y = 4, simply replace y-term to 4.

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If you have any doubts regarding my answer/explanation, do not hesitate to ask in comment!
Answer: 0.84134
Step-by-step explanation:
We need to find the z-score for the given information first since this will help us find the probability. The formula for this is
Z score = 
We have
66 inches (the raw score)
70 inches (the population mean)
= 4 inches (the standard deviation)
This gives
Z score =
= 
If you use a calculator, or a Z-score table then P(x > Z) is just P(Z > -1) which gives a probability of 0.84134.