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.

y + 9 = \( \frac{y}{-8} \)
-8 x (y + 9) = y
(-8 x y) + (-8 x 9) = y
-8y - 72 = y
-8y - 72 - y = 0
-8y - y = 72
-9y = 72
y = \( \frac{72}{-9} \)
y = -8

To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.

8a + 7a = 15a

To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.

(7a)(6ab) - (3a²)(6b)
(7 x 6)(a x a x b) - (3 x 6)(a² x b)
(42)(a¹⁺¹ x b) - (18)(a²b)
42a²b - 18a²b
24a²b

The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, 1) and (2, 3) so the slope becomes:

The area of a rectangle is equal to its length x width:

a = l x w
a = a x b
a = 8 x 7
a = 56