Answer :

Certainly! Let's solve the given equation step by step:

[tex]\[ \frac{a + 5d}{a} = \frac{a + 11d}{a + 5d} \][/tex]

Step 1: Cross-multiply to eliminate the fractions.

[tex]\[ (a + 5d)(a + 5d) = a(a + 11d) \][/tex]

Step 2: Expand both sides of the equation.

[tex]\[ (a + 5d)(a + 5d) = a^2 + 10ad + 25d^2 \][/tex]
[tex]\[ a(a + 11d) = a^2 + 11ad \][/tex]

Step 3: Set the expanded forms equal to each other.

[tex]\[ a^2 + 10ad + 25d^2 = a^2 + 11ad \][/tex]

Step 4: Subtract [tex]\(a^2\)[/tex] from both sides to simplify.

[tex]\[ 10ad + 25d^2 = 11ad \][/tex]

Step 5: Subtract [tex]\(10ad\)[/tex] from both sides to further simplify.

[tex]\[ 25d^2 = ad \][/tex]

Step 6: Divide both sides by [tex]\(d\)[/tex] (assuming [tex]\(d \neq 0\)[/tex]) to isolate [tex]\(a\)[/tex].

[tex]\[ 25d = a \][/tex]

So the solution for [tex]\(a\)[/tex] in terms of [tex]\(d\)[/tex] is:

[tex]\[ a = 25d \][/tex]

Therefore, the value of [tex]\(a\)[/tex] that satisfies the original equation is:

[tex]\[ a = 25d \][/tex]