Answer
a. $\frac{d+2}{4}=n$
b.
Penny size $=3$, length of the nail $=1.25$ inches.
Penny size $=6$, length of the nail $=2$ inches.
Penny size $=10$, length of the nail $=3$ inches.
Work Step by Step
The given literal equation is
$\Rightarrow d=4n-2$
a.
$\Rightarrow d=4n-2$
Add $2$ to each side.
$\Rightarrow d+2=4n-2+2$
Simplify.
$\Rightarrow d+2=4n$
Divide each side by $4$.
$\Rightarrow \frac{d+2}{4}=\frac{4n}{4}$
Simplify.
$\Rightarrow \frac{d+2}{4}=n$ ...... (1)
b.
Substitute 3 for $d$ in the equation (1).
$\Rightarrow \frac{3+2}{4}=n$
Simplify.
$\Rightarrow \frac{5}{4}=n$
$\Rightarrow 1.25=n$
Substitute 6 for $d$ in the equation (1).
$\Rightarrow \frac{6+2}{4}=n$
Simplify.
$\Rightarrow \frac{8}{4}=n$
$\Rightarrow 2=n$
Substitute 10 for $d$ in the equation (1).
$\Rightarrow \frac{10+2}{4}=n$
Simplify.
$\Rightarrow \frac{12}{4}=n$
$\Rightarrow 3=n$
