# The equation is 13k = 6k/15t - 7t Make k the subject?

### 5 Answers

- KrishnamurthyLv 71 year ago
13 k = 6 k/15 t - 7t

13 k = (2 k t)/5 - 7 t

65 k = t (2 k - 35)

k(65 - 2 t) = -35 t

k

= -35 t / (65 - 2 t)

= 35 t / (2 t - 65)

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- ?Lv 71 year ago
13k = 6k/15t - 7t

// Multiply through by 15t

13k (15t) = 6k - 7t (15t)

195 kt - 6k = - 105 t²

// Factor out k

k (195t - 6) = -105 t²

// Divide through by (195t - 6)

k = -105 t² / (195t - 6)....................ANS

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- ComoLv 71 year ago
Presentation is open to doubt due to lack of brackets.

- Random StrangerLv 61 year agoReport
No it isn't! That's why we use the order of operations, to prevent ambiguity. Asker my have asked the wrong question but what was asked is NOT in doubt.

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- RaymondLv 71 year ago
I assume that the - 7t is a separate term

in other words, your equation is NOT:

13k = 6k / (15t - 7t)

-----

13k = (6k/15t) - 7t

multiply both sides by (15t)

(13k)(15t) = 6k - (15t)(7t)

clean up

195kt = 6k - 105t^2

subtract 6k from both sides

195kt - 6k = -105t^2

factor out "k" on the left

k(195t - 6) = -105t^2

divide both sides by (195t - 6)

k = (-105t^2) / (195t - 6)

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- llafferLv 71 year ago
Presuming you mean:

13k = 6k/(15t) - 7t

Since "k" is in more than one term, we need to group them together. Start with multiplying both sides by the denominator (15t):

195kt = 6k - 105t²

Now move the terms with "k" to one side and all other terms to the other side:

195kt - 6k = -105t²

to simplify a little, multiply both sides by -1. I'll flip the two terms around the subtraction on the left side:

6k - 195kt = 105t²

And now I can divide both sides by 3 to simplify further before we move on:

2k - 65kt = 35t²

Now we can factor out the k:

k(2 - 65t) = 35t²

and divide:

k = 35t² / (2 - 65t)

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