
Sean M. answered 10/31/19
Eagle Scout tutoring in Algebra, Statistics, Calculus, and Java
Once they combine like terms they will have
8x+11=27
the "subtraction property of equality" is just subtracting the same thing on both sides (in this case 11)
8x+11-11=27-11
after combining those like terms (left sides adds to zero, right side to 16)
8x=16
The "division property of equality" is just dividing the same thing on both sides (in this case 8)
8x/8=16/8
Then we simplify one last time to get...
x=2
"An equation that contains fractions". Well let's think about it with a simple equation
y = 1/2x
x=0 gets us 0
x = 1 gets us 1/2
x=2 gets us 1
Furthermore I can say that 1/1 is a fraction and 2/1 is a fraction, but those are the same as 1 and 2
The answer is sometimes. Whenever you see something in math that is NEVER or ALWAYS, be very careful. Its easy to disprove them with one example, while proving them is a lot harder.
To check the solution of an equation...
Let's say we have the first equation
3x+7+5x+4=27
Once you have a final answer (x=2), you can substitute (plug in) the solution for its variable (in this case x)
Replacing it we get...
3(2) + 7 + 5(2) + 4 = 27
Then we do multiplication and addition for each side and see if the equation is true
6 + 7 + 10 + 4 = 27
13 + 14 = 27
27 = 27
Its true, because 27 is equal to 27. If we had 23=27 or any simplified number besides 27 that would be false.