Answer:
a=-7
Explanation:
since the bases are the same we're going to set the exponents equal so your equation would be: 2a+3=a-4
next you're going to move the variable to the left and change its sign(=a to -a)
then you're going to move the constant to the right and change its sign(+3 to -3)
your equation should be 2a-a=-4-3
then collect like terms:
2a-a=a
-4-3=-7
so your final answer is a=-7