Answer two questions about Equations and : A.3(x+2)=18B. x+2=6\begin{aligned} A.&&3(x+2)&=18 B.&&x+2&=6 \end{aligned}A. B.3(x+2)x+2=18=6
1) How can we get Equation from Equation ?
Choose 1
Choose 1

(Choice A)
A
Add/subtract the same quantity to/from both sides
(Choice B)
B
Add/subtract a quantity to/from only one side
(Choice C)
C
Multiply/divide both sides by the same non-zero constant
(Choice D)
D
Multiply/divide only one side by a non-zero constant

2) Based on the previous answer, are the equations equivalent? In other words, do they have the same solution?
Choose 1
Choose 1

(Choice A)
A
Yes
(Choice B)
B
No

Choice D

(hope it helps!)

step-by-step explanation:

30% of $420 is 0.30($420) = $126 and $420 + $126 = $546.

or, 130% of $420 is 1.3($420) = $546.

notice that this is not the $600 original list price with which we started.

why doesn't this work?

the method does not work because 30% of $420 is not the same amount as the 30% of $600. it may seem obvious when stated this way, but it is a very common error made on problems of this type. we cannot just use the same percent and get back to the original amount because we are taking that percent of a different value.

to work problems of this type correctly, it is generally best to write an equation for the situation and then solve.

example: since (100% – 30%)(original price) = (sale price)

70% of the   (original price) is $420.

0.7x   = 420

equation image indicator

x = 600

the original cost was $600.

we may also solve this problem using the two-step method. working the problem in two steps requires us to use more algebra skills. we have to know that x = 1x (identity property of multiplicationtext annotation indicator) and that 1x – 0.3x = 0.7x (subtracting like terms). then we solve the problem as follows:

(original price) – 30%(original price) = sale price

x – 0.3x = 420

0.7x = $420

equation image indicator

x = 600

the original cost was $600.  

note that with both of the above methods we do obtain the correct original amount.

example: after a 5% pay raise, hermione is earning $22,680 per year. what was she earning before the pay raise?

105% of (original salary) = current salary

1.05x = 22,680

equation image indicator

x = 21,600

hermione earned $21,600 per year before the pay raise.

this is an example so maybe you will get how to at least do it!

45

step-by-step explanation:

to find a percentage, add a decimal in front and multiply it by the other number.

.25 times 180= 45