Answer: Choice C and Choice D
========================================================
Explanation:
- Choice A doesn't work because it the $1 should be $7 instead.
- Choice B doesn't work because it should be Elena spending $7 total on 3 notebooks and a $1 pen. The x is the amount per notebook.
- Choice C does work. If x is the number of grapes Noah gives each friend, then 3x is the total amount Noah gives over. Then 3x+1 is the number of grapes total. That +1 at the end is the grape Noah eats. We end up with 3x+1 = 7 because Noah starts off with 7 grapes.
- Choice D works also. The x is the number of hours for math, science and history each. So 3x is the combined time of those three classes. Add on 1 to get 3x+1 to represent all 7 hours, ie 3x+1 = 7.
- Choice E does not work. If it was her spending $7 on 3 markers and a $1 pen, then it would work.
Answer:
The area of the figure composed of a parallelogram, a square and a rectangle is 126 in².
Step-by-step explanation:
Hope I could help!
Answer:
17.37
Step-by-step explanation:
y varies inversely as the square root of x
Mathematically:
y = k.root x
We first find k here
To find k, we were made to know that y is 21 and x = 361
k = y/root.x
k = 21/root. 361
k = 21/19
now what is y when x = 247
From y = k.root x
y = 21/19 * root 247
y= 21/19 * 15.72
y = 17.37
Answer: (7, 20)
Concept:
There are three general ways to solve systems of equations:
- Elimination
- Substitution
- Graphing
Since the question has specific requirements, we are going to use <u>substitution </u>to solve the equations.
Solve:
<u>Given equations</u>
y = 3x - 1
2x + 6 = y
<u>Substitute the y value since both equations has isolated [y]</u>
2x + 6 = 3x - 1
<u>Add 1 on both sides</u>
2x + 6 + 1 = 3x - 1 + 1
2x + 7 = 3x
<u>Subtract 2x on both sides</u>
2x + 7 - 2x = 3x - 2x

<u>Find the value of y</u>
y = 3x - 1
y = 3(7) - 1
y = 21 - 1

Hope this helps!! :)
Please let me know if you have any questions
Answer:
(y-4)(y+4)
Step-by-step explanation:
When you factor the y^2 you need to factor the rest of your equation. Your K does not exist since it is a perfect square and there is no c. Then you square 16 which is 4 so you have (y-4) (y+4). Hope this helps :)