Solve for x 5/3 = 1/2(x^-1)(y)

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To solve the equation 5/3 = 1/2(x^-1)(y), the initial step involves multiplying both sides by x to eliminate the x^-1 term. This leads to the equation 5/3x = 1/2y, which can be rearranged to find y in terms of x as y = 10/3x. The next step is to substitute this expression for y back into the original equation to isolate x. Ultimately, the solution simplifies to x = 3y/10, confirming the relationship between x and y. The discussion emphasizes the importance of understanding how to manipulate equations involving multiplication and division.
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Homework Statement



Solve for x. I know how to do this when there is addition and subtraction but I'm confused what to do when there is multiplication. Sorry for the newb question...

Homework Equations



5/3 = 1/2(x^-1)(y)

The Attempt at a Solution



10/3 = (x^-1)(y)
(10/3)/(y) = (x^-1)
 
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939 said:

Homework Statement



Solve for x. I know how to do this when there is addition and subtraction but I'm confused what to do when there is multiplication. Sorry for the newb question...

Homework Equations



5/3 = 1/2(x^-1)(y)
Is this 5/3 = 1/2 * x-1 * y?

If so, for starters, multiply both sides of the equation by x.
939 said:

The Attempt at a Solution



10/3 = (x^-1)(y)
(10/3)/(y) = (x^-1)
 
Mark44 said:
Is this 5/3 = 1/2 * x-1 * y?

If so, for starters, multiply both sides of the equation by x.
Yes, it is, sorry...

5/3(x) = (1/2)*(y)
then... divide both sides by 5/3?

x = 3/10(y)
 
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939 said:
Yes, it is, sorry...

5/3(x) = (1/2)*(y)
then... divide both sides by 5/3?

x = 3/10(y)
Right, but this would be clearer as 3y/10.
If you write it as you did, some might (mistakenly) think you meant 3/[10y].

Also, dividing by 5/3 is the same as multiplying by 3/5, the reciprocal of 5/3.
 
Mark44 said:
Right, but this would be clearer as 3y/10.
If you write it as you did, some might (mistakenly) think you meant 3/[10y].

Also, dividing by 5/3 is the same as multiplying by 3/5, the reciprocal of 5/3.

Got it. Thanks yet again.
 
You are trying to solve for x so my approach would be to solve to y in terms of x and then plug that into y so there is only x in the equation and then solve for x, so

5/3 = 1/2 * x^-1 * y
Multiply both sides by x as you did before
5/3x = 1/2 * y
Divide both sides by 1/2
10/3x = y

Now plug that into the original equation for y and then solve for x.

5/3 = 1/2 * x^-1 * (10/3x)

Solve for x. If my math is wrong please correct me, it's been some time since I done a problem like this.
 
SpaceDreamer said:
You are trying to solve for x so my approach would be to solve to y in terms of x and then plug that into y so there is only x in the equation and then solve for x, so

5/3 = 1/2 * x^-1 * y
Multiply both sides by x as you did before
5/3x = 1/2 * y
Divide both sides by 1/2
10/3x = y

Now plug that into the original equation for y and then solve for x.

5/3 = 1/2 * x^-1 * (10/3x)

Solve for x. If my math is wrong please correct me, it's been some time since I done a problem like this.
Do that and you'll find that 5/3 = 5/3.
 
SpaceDreamer said:
You are trying to solve for x so my approach would be to solve to y in terms of x and then plug that into y so there is only x in the equation and then solve for x, so

5/3 = 1/2 * x^-1 * y
Multiply both sides by x as you did before
5/3x = 1/2 * y
Divide both sides by 1/2
Since the instructions are to solve for x, it's a waste of time to solve for y first. All you need to do is get rid of the 5/3 coefficient of x, which you can do by multiplying both sides by 3/5. This leaves you with x = 3y/10, as before.
SpaceDreamer said:
10/3x = y

Now plug that into the original equation for y and then solve for x.

5/3 = 1/2 * x^-1 * (10/3x)

Solve for x. If my math is wrong please correct me, it's been some time since I done a problem like this.
 
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