Hello!
For ALL of the equations, you want to solve for the variable (letter) and get it by itself. So,
#1- The equation is 3n + 5 = 6. We want to subtract 5 from the left side, so 3n can be by itself. BUT, if we subtract 5 from the left, we also need to do it to right side. The equation is now: 3n = 1. We then want "n" by itself, so we need to divide "n" by 3 to get "n" by itself. Again, if we do it to the left side, we need to do it to the right. After you simplify, the equation simplifies to: n = 1/3 (in decimal form, the decimal would be repeating {0.33333}).
#2- The equation is 4 + 5x = 1. To get "5x" by itself on that side, let's subtract 4 to that side and the right side. After you do that, it'll be: 5x = -3. Then divide "x" by 5 to each side. The answer is: x= -3/5 (-0.6).
#3- The equation is 4y - 15 = -10. If we want "4y" by itself, we will do the opposite of subtracting 15 to adding 15 to both sides. After you do that, it'll be: 4y = 5. To finish it off, divide "y" by 4 to both sides. That will get you with:
y = 5/4 (1.25).
#4- The equation is 3 - 4d = 13. To get 4d by itself, let's subtract 3 to each side. That'll leave you with: -4d = 10. Now divide d by "-4" to both sides. The answer is: d = -10/4 (-2.5).
#5- The equation is 8 = 9x - 7. Let's add 7 to each side so that 9x can be by itself. After we do that, it's simplified to: 15 = 9x. Finish it off by dividing "x" by 9 to both sides. That'll leave you with the answer: x = 15/9 (in decimal form, this decimal would be repeating {1.66666}).
Anyone can fix my mistakes if they are wrong. I hope this helps!
May