9514 1404 393
Answer:
d. 45
Step-by-step explanation:
You can check the offered answers. You will find that the difference from reversing the digits will only be 9 if the digits differ by 9/9 = 1.
The original number is 45.
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<em>Check</em>
45 + 9 = 54 . . . with the digits reversed
Answer: ![(-9, 16]](https://tex.z-dn.net/?f=%28-9%2C%2016%5D)
This is the interval from -9 to 16. Exclude -9 but include 16.
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Work Shown:
The idea is to multiply all sides by 5, then add 1 to all sides
This converts to the interval notation
note: a curved parenthesis means "do not include this value in the solution set"; while a square bracket has us include the value. So we exclude -9 and include 16.
Answer:
C. 3, -7
Step-by-step explanation:
x^2 +4x-21 =0
Factor
What 2 numbers multiply to -21 and add to 4
7*-3 = -21
7-3 = 4
(x+7) (x-3) =0
Using the zero product property
x+7 =0 x-3=0
x+7-7=0-7 x-3+3=0+3
x = -7 x=3
Answer:
"subtracting b, then dividing by m"
Step-by-step explanation:
To solve for a particular variable, look a the operations that are being performed on that variable. Then "undo" those operations in reverse order.
Here, the operations done to x are ...
• multiply by m
• add b to the product
Using the above recipe, first we "undo" the additon of b. We accomplish that by subtracting b from both sides of the equation. This gives ...
y - b = mx + b - b
y - b = mx . . . . . . . . . simplify
Next, we "undo" the multiplicatin by m. We accomplish that by dividing both sides of the equation by m.
(y -b)/m = mx/m
(y -b)/m = x . . . . . . . . simplify
This is your solution for x:
x = (y - b)/m
We found it by subtracting b, then dividing by m on both sides of the equation.
Answer:
-b=11
Step-by-step explanation:
Nothing else is equal to a number except its self
