To do this, I simply inverted each value for "hours to complete job": My first step is to list the times taken by each pipe to fill the pool, and how long the two pipes take together.
In this case, I know the "together" time, but not the individual times.
One of the pipes' times is expressed in terms of the other pipe's time, so I'll pick a variable to stand for one of these times. Since the faster pipe's time to completion is defined in terms of the second pipe's time, I'll pick a variable for the slower pipe's time, and then use this to create an expression for the faster pipe's time: Then I make the necessary assumption that the pipes' contributions are additive (which is reasonable, in this case), add the two pipes' contributions, and set this equal to the combined per-hour rate: Note: I could have picked a variable for the faster pipe, and then defined the time for the slower pipe in terms of this variable.
If you're not sure how you'd do this, then think about it in terms of nicer numbers: If someone goes twice as fast as you, then you take twice as long as he does; if he goes three times as fast as you, then you take three times as long as him.
So if we multiply the right-hand side by 4, we also have to multiply the left-hand side by 4.
So we get 4 times negative 18 is equal to x over 4, times 4. You divide something by 4 and multiply by 4, you're just going to be left with an x. is the third math course in high school and will guide you through among other things linear equations, inequalities, graphs, matrices, polynomials and radical expressions, quadratic equations, functions, exponential and logarithmic expressions, sequences and series, probability and trigonometry.This is divided into 13 chapters and each chapter is divided into several lessons.There are a lot of computer-based algebra solvers out there, but for Socratic they had to do some extra engineering to get at the steps a human would need to solve the same problem.Also, I'd be remiss not to mention Photomath, which has been doing this since 2014, and actually has step-by-step explanations in the recently released Photomath paid version (there's a free trial).If you're behind a web filter, please make sure that the domains *.and *.are unblocked.We have the equation negative 16 is equal to x over 4, plus 2. So we really just need to isolate the x variable on one side of this equation, and the best way to do that is first to isolate it-- isolate this whole x over 4 term from all of the other terms.Many of these problems are not terribly realistic — since when can two laser printers work together on printing one report?— but it's the technique that they want you to learn, not the applicability to "real life". I was homeschooled (that's not the confession part), and in 8th grade my algebra textbook had the answers to half the problems in the back. That seems to be the premise behind app called Socratic. The app lets you take a picture of a problem (you can also type it in, but that's a little laborious), and it'll not only give you an answer, but the steps necessary to to arrive at that answer — and even detailed explanations of the steps and concepts if you need them. Of course, cheating at math is a terrible way to learn, because the whole point isn't to know the answer to 2x 2 = 7x - 5, it's to understand the learn?