9514 1404 393
Answer:
(a) 1. Distributive property 2. Combine like terms 3. Addition property of equality 4. Division property of equality
Step-by-step explanation:
Replacement of -1/2(8x +2) by -4x -1 is use of the <em>distributive property</em>, eliminating choices B and D.
In step 3, addition of 1 to both sides of the equation is use of the <em>addition property of equality</em>, eliminating choice C. This leaves only choice A.
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<em>Additional comment</em>
This problem makes a distinction between the addition property of equality and the subtraction property of equality. They are essentially the same property, since addition of +1 is the same as subtraction of -1. The result shown in Step 3 could be from addition of +1 to both sides of the equation, or it could be from subtraction of -1 from both sides of the equation.
In general, you want to add the opposite of the number you don't want. Here, that number is -1, so we add +1. Of course, adding an opposite is the same as subtracting.
In short, you can argue both choices A and C have correct justifications. The only reason to prefer choice A is that we usually think of adding positive numbers as <em>addition</em>, and adding negative numbers as <em>subtraction</em>.
Hello!
You can make two expressions based on what you know
let x equal the larger number
let y equal the smaller number
x + y = 95
x + 2y = 120
We can use elimination to get rid of x
You can subtract the two equation to get rid of x
-y = -25
Since y is negative we can multiply both sides by -1 to make y positive
y = 25
Now we can put this into one of the other equations to find x
x + 25 = 95
subtract 95 from both sides
x = 70
The answers are 70 and 25
Hope this helps!
1/2. If you take out the units you're left with 5 to 10 or 5/10. 5 is half of 10 therefore the simplest form would be 1/2.
Yeah you did it right but good job!
It asks to "Find the unit price in dollars per padlock"
The phrasing "dollars per padlock" is the same as "dollars per 1 padlock"
In other words, the teacher wants to know how much 1 padlock costs.
7 padlocks : $23.80
7/7 padlocks : $23.80/7 .... divide both parts by 7
1 padlock : $3.40
We see that 1 padlock costs $3.40, so the unit cost is $3.40 per padlock