# Thread: Help with irrational equations.

1. ## Help with irrational equations.

√(4x-20)+√(x-5)-1/5*√(9x-45)=4

and

4^√(x+15)-√(x-1)=2

I need these simplified or solved if possible for my homework.

2. ## Re: Help with irrational equations.

They will NOT be solved for you, students are expected to be doing their own work. We are here to provide you with guidance, not do your homework for you.

Also it helps if your equations can actually be read. The first one I think I can make out, is it \displaystyle \begin{align*} \sqrt{ 4x- 20} + \sqrt{ x - 5} - \frac{1}{5} \sqrt{9x - 45} = 4 \end{align*}? The second one I have no clue, some more brackets would be nice...

3. ## Re: Help with irrational equations.

√(4x-20)+√(x-5)-1/5*√(9x-45)=4

You could start this problem by factoring all in brackets and you should notice a common factor of (x-5)

Take it from here.

try it for yourself before coming back for further help. Remember maths is a 'doing' subject not a 'reading or listening to somebody else' subject.
Good luck but dpo not hesitate for further guidance.

4. ## Re: Help with irrational equations.

Originally Posted by Seljak76
√(4x-20)+√(x-5)-1/5*√(9x-45)=4

and

4^√(x+15)-√(x-1)=2

I need these simplified or solved if possible for my homework.
Check out wolframalpha.com. Type in something like "Solve for x: SQRT(4x-20) + SQRT(x-5) -1/5*SQRT(9x-45) = 4" and if there is a solution, it will give it to you. It even has an option to see the step-by-step solution. For problems like these, practice is the only way to learn. But, seeing a step-by-step solution for one problem can help you see patterns that will help you to solve future problems. Rather than plug in your homework problems, maybe plug in some problems that are not for homework and see the step-by-step solution. Then, try your homework problems yourself. If necessary, you can always plug in your homework problems to see if you got the right answer.

5. ## Re: Help with irrational equations.

Originally Posted by Seljak76
√(4x-20)+√(x-5)-1/5*√(9x-45)=4
\displaystyle \begin{align*} \sqrt{ 4x- 20} + \sqrt{ x - 5} - \frac{1}{5} \sqrt{9x - 45} &= 4\\5\sqrt{ 4x- 20} + 5\sqrt{ x - 5} - 3\sqrt{x - 5} &= 20\\5\sqrt{ 4x- 20} + 2\sqrt{ x - 5} &= 20 \end{align*}

6. ## Re: Help with irrational equations.

Originally Posted by Plato
\displaystyle \begin{align*} \sqrt{ 4x- 20} + \sqrt{ x - 5} - \frac{1}{5} \sqrt{9x - 45} &= 4\\5\sqrt{ 4x- 20} + 5\sqrt{ x - 5} - 3\sqrt{x - 5} &= 20\\5\sqrt{ 4x- 20} + 2\sqrt{ x - 5} &= 20 \end{align*}
And even

\displaystyle \begin{align*} 10\sqrt{x - 5} + 2\sqrt{x - 5} &= 20 \\ 12\sqrt{x - 5} &= 20 \end{align*}

etc...