Answer:
A
Step-by-step explanation:
First, you have to align the like terms next to each other so that it will be easier to combine like terms. (Like terms have the same variables and powers)
Combine like terms:
(When combining like terms all you have to do is add/subtract the coefficients, number in front of variables, and leave the variable and exponents)
So, we get 
4x - 9 = 2x
Solve for x.
4x = 2x + 9
2x = 9
x = 4.5
We can plug 4.5 into the original equation to verify if it's correct.
4x - 9 = 2x
4(4.5) - 9 = 2(4.5)
18 - 9 = 9
The equation is true, and so x = 4.5
Answer:
15 meters
Step-by-step explanation:
The volume of a cylinder is:
pi is a constant, so there are only 3 variables in this equation. 2 of those are given, so all you need to do is plug in the given values and solve for h:
The height of this cylinder is 15 meters.
Answer:
The number is 72.
Step-by-step explanation:
Let the digits be x and x - 5 where x is the first digit.
(As the number reversed = 3/8 of the original number the first digit must be the largest),
Consider the reverse digit number:
The original number = 10x + (x - 5) so the reverse number is 10(x - 5) + x and
10(x - 5) + x = 3/8(10x + (x - 5))
11x - 50 = 3/8(11x - 5)
11x - 50 = 33/8 x - 15/8 Multiply through by 8:
88x - 400 = 33x - 15
55x = 385
x = 7
and x-5 = 2.
Answer:
-4+6(3-n)=6n-14
Step-by-step explanation:
Distributive property and then simplify
