Is this your equation?: 4.5x - 7 = 20 _____________________________________________________________
Your goal is to isolate x. By isolating the x-variable, you effectively receive the answer. In order to isolate x, you move the -7 term [Note: that the sign in front of a number signifies if it's positive or negative] as well as 4.5 behind the equality symbol. To do this, you do reverse operations to both sides. Start with -7.
The opposite of negative 7 is positive 7, therefore -7 + 7 = 20 + 7 -7 + 7 cancels each other out and 27 takes the place of 20. We now have: 4.5x = 27
Since you have to multiply 4.5 by x originally, you have to divide now. Divide 4.5 by itself and 27 by 4.5. This gives you 1 and 6. [Note that a 1 in front of a variable is like saying only that variable]
(1)x = 6, Therefore x is equivalent to 6.
Briefly check your work by taking the original equation and substituting x with 6. If 4.5(6) - 7 equals 20, 6 is our right answer. [Note: Solve with PEMDAS]
The statement reports the investment's value has gone up. That is inconsistent with a negative rate of return, which would mean the value has gone down.
No, the reported rate of return does not seem reasonable.
The positive trend among the homework scores and the test scores would reveal that if a student does well in homework, he is likely to do well in exams. This can be explained in the sense that the homework will serve as the practice for the student before finally taking the exam.
