Answer
$z=3.75$
Work Step by Step
Given the equation:
$5(2+4z)=85$
We start by opening up the brackets as shown below:
$10 + 20z = 85$
Next, isolate the variable $z$ by subtracting $10$ from both sides of the equation as shown below:
$10 + 20z - 10 = 85 - 10$
Simplify to get:
$20z = 75$
Divide through by the coefficient of the variable $z$ as shown below:
$\frac{20}{20}z = \frac{75}{20}$
Simplify to get:
$z = \frac{15}{4}$
Simplifying further, we have:
$z = 3\frac{3}{4}$
This is equivalent to:
$z = 3.75$
