When solving an equation with two variables, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)

The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:

z² - 16 = 0
(z - 4)(z + 4) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (z - 4) or (z + 4) must equal zero:

If (z - 4) = 0, z must equal 4
If (z + 4) = 0, z must equal -4

So the solution is that z = 4 or -4

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 < sign and the answer on the other.

-7b + 6 < -5 - 2b
-7b < -5 - 2b - 6
-7b + 2b < -5 - 6
-5b < -11
b < \( \frac{-11}{-5} \)
b < 2\(\frac{1}{5}\)

The volume of a cube is height x length x width:

v = h x l x w
v = 5 x 3 x 4
v = 60

The perimeter of a triangle is the sum of the lengths of its sides:

p = x + y + z
p = 9cm + 14cm + 6cm = 29cm