When x is equal to what number, the monomial 5A ^ 2x + 1 and 8A ^ x + 3 are of the same kind

When x is equal to what number, the monomial 5A ^ 2x + 1 and 8A ^ x + 3 are of the same kind

The monomials 5A ^ 2x + 1 and 8A ^ x + 3 are of the same kind
2x+1=x+3
x=2

5a+0.7ax=0.8a（5+x）
What is x equal to

Both sides divide by a, 5 + 0.7x = 4 + 0.8x
X = 10 (a is not equal to 0)

a^3+3a^2+a=0 5a^2/a^4+8a^2+1=?

So: 5A ^ 2 / (a ^ 4 + 8A ^ 2 + 1) = 0 or 1 / 3. 0 is easy to understand, the following is the derivation process of 1 / 3: take a ^ 2 = - 1-3a into the formula: 5A ^ 2 / (a ^ 4 + 8A ^ 2 + 1) = - 5-15a / (a ^ 4 + 8A ^ 2 + 1) = - 5-15a / (- 5