To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.

6y - 1 = -8 + y
6y = -8 + y + 1
6y - y = -8 + 1
5y = -7
y = \( \frac{-7}{5} \)
y = -1\(\frac{2}{5}\)

An equation is two expressions separated by an equal sign. The key to solving equations is to repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.

To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.

c - 7 = \( \frac{c}{-3} \)
-3 x (c - 7) = c
(-3 x c) + (-3 x -7) = c
-3c + 21 = c
-3c + 21 - c = 0
-3c - c = -21
-4c = -21
c = \( \frac{-21}{-4} \)
c = 5\(\frac{1}{4}\)

The entire length of this line is represented by AD which is AB + BD:

AD = AB + BD

Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are supplementary (they add up to 180°) and angles across from either other are vertical (they're equal).