Answer:
Step-by-step explanation:
Let age of each twin be x
let age of sister be s
So we can write:
x + 4 = s
The product of the 3 siblings ages is 3482 more than sum. We can write:
This can be simplified as:
We replace s with "x + 4" and solve:
<u>Note:</u> To solve this cubic, we used technology
Thus, we can say the twins are 14 years old
Solution:
<em>Simple Interest = Principal Amount × Rate of Interest/100 × Time</em>
Here, Principal Amount = $6000
Rate of Interest = 6%
Time = 4 years
Simple Interest = 6000 × 6/100 × 4 = <em>$1440</em>
Answer:
The sales price is 90% of the regular price.
The regular price is $60
10% of 60 is $6
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>.
