Question

Pick out the solution from the values given in the bracket next to each question. Show that the other values do not satisfy the equation:
$4m+5=21(1,5,4)$

Answer 1

$4m+5=21(1,5,4)$
First we put $m=1$ in L.H.S of equation:
We get-
$$\begin{gathered} =4\times 1+5 \\ =4+5 \\ =9 \end{gathered}$$
Therefore L.H.S is not equals to R.H.S.

Next we put $m=5$ in L.H.S of equation:
we get:
$$\begin{gathered} =4\times 5+5 \\ =20+5 \\ =25 \end{gathered}$$
Therefore L.H.S is not equals to R.H.S.
Next we put $m=4$ in L.H.S of equation:
We get:$$\begin{gathered} =4\times 4+5 \\ =16+5 \\ =21 \end{gathered}$$
Therefore $L.H.S=R.H.S$
We find that $L.H.S=R.H.S$ when $m=4$, hence the solution is $m=4$.