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 Question from Monejah, a student: I need help solving 8t-r=12t for t

Hi Monejah,

Solve it first with a specific value for $r,$ say $r = 7.$

Solve $8t - 7 = 12t$ for $t.$

You want to isolate $t$ on the left of the equality sign so you need to remove the term $12t$ from the right side. To do this add $-12t$ to both sides of the equation to get

$8t - 7 - 12t = 12t - 12t$

simplifying gives

$-4t - 7 = 0$

Now add 7 to each side to get

$-4 t = 7$

Finally multiply each side by $\large - \frac14$ to get

$- \frac14 \times -4 t = - \frac14 \times 7$

or

$t = - \frac74$

Now mimic these steps to solve $8t - r = 12t$ for $t.$

Penny

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