Answer:
3. n = 2
4. t = -13/4
Explanation:
3)
. . . . (3a) Distribute (multiply) +5 into the expression (n-1)
. . . . . . . .
![n + 5n - 5 = 7](https://img.qammunity.org/2023/formulas/mathematics/high-school/cae95ipzhnlghikf3a658hgyq0c00okr8n.png)
. . . . (3b) Add like terms (terms with the same variable)
. . . . . . . .
![6n - 5 = 7](https://img.qammunity.org/2023/formulas/mathematics/high-school/2g0roh2zm187j1ju7v5mqxx1mdu2559i5t.png)
. . . . (3c) Add 5 on both sides of the equation to "get rid" of the -5
. . . . . . . .
![6n -5 +5 = 7 +5](https://img.qammunity.org/2023/formulas/mathematics/high-school/wr1ugh0wf2mvszjt2ydaw9pdxfk647hm1t.png)
. . . . . . . .
![6n = 12](https://img.qammunity.org/2023/formulas/mathematics/high-school/nyudtswj7166xeed3f33jqikq29t5vwuk9.png)
. . . . (3d) Divide both sides by 6 to isolate the variable
. . . . . . . .
![6n/6 = 12/6](https://img.qammunity.org/2023/formulas/mathematics/high-school/h7cic73dom7o4af86yo9i9wzvc0ajcji2q.png)
. . . . . . . .
![n = 2](https://img.qammunity.org/2023/formulas/physics/college/hwy720q4onfybtya725izn3r8ou33p523s.png)
4)
. . . . (4a) Distribute (multiply) -2 into the expression (2t-1)
. . . . . . . .
![15 = -4t + 2](https://img.qammunity.org/2023/formulas/mathematics/high-school/15zadvdbrezga9divl9gc3ayai9ph76ltt.png)
. . . . (4b) Subtract 2 on both sides of the equation to "get rid" of the +2
. . . . . . . .
![15 -2 = -4t +2 -2](https://img.qammunity.org/2023/formulas/mathematics/high-school/mgkdqf5btw360p90v3gc05u3zlwe9ildq7.png)
. . . . . . . .
![13 = -4t](https://img.qammunity.org/2023/formulas/mathematics/high-school/xnrpmcn1a55y6bfykmrbzsvd83vo7n44d5.png)
. . . . (4c) Divide both sides by -4 to isolate the variable
. . . . . . . .
![13/-4 = -4t/-4](https://img.qammunity.org/2023/formulas/mathematics/high-school/yssrgwz0rzny61s2or8367dow7dluwk45z.png)
. . . . . . . .
![-13/4 = t](https://img.qammunity.org/2023/formulas/mathematics/high-school/lj97gylptem5vh2eiuxkl3tb2ak8ymzdl5.png)