moet ik dit kunnen snappen?

Gegeven is de formule $N=\frac{{\Large20k + 30}}{{\Large4m + 1}}$

  1. Neem $m=1$ en druk $N$ uit in $k$.
  2. Neem $k$=4. Voor welke $m$ is $N=11$?
  3. Neem $N=5$ en schrijf $m$ in de vorm $m = ak + b$.

a.

$
\begin{array}{l}
N = \frac{{\Large20k + 30}}{{\Large4 \cdot 1 + 1}} \\
N = \frac{{\Large20k + 30}}{{\Large4 + 1}} \\
N = \frac{{\Large20k + 30}}{\Large5} \\
N = \frac{{\Large20k}}{\Large5} + \frac{{\Large30}}{\Large5} \\
N = 4k + 6 \\
\end{array}
$

b.

$
\begin{array}{l}
 11 = \frac{{\Large20 \cdot 4 + 30}}{{\Large4m + 1}} \\
 11 = \frac{{\Large80 + 30}}{{\Large4m + 1}} \\
 11 = \frac{{\Large110}}{{\Large4m + 1}} \\
 11(4m + 1) = 110 \\
 4m + 1 = 10 \\
 4m = 9 \\
 m = 2\frac{1}{4} \\
 \end{array}
$

c.

$
\begin{array}{l}
 5 = \frac{{\Large20k + 30}}{{\Large4m + 1}} \\
 5(4m + 1) = 20k + 30 \\
 20m + 5 = 20k + 30 \\
 20m = 20k + 25 \\
 m = k + 1\frac{1}{4} \\
 \end{array}
$

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