3*4^x + 5 * 4^x-3 =197

Question

3*4^x + 5 * 4^x-3 =197

Answer 1

3*4^x+5*4^x*4^-3=197
4^x(3+5*1/64)=197
4^x *(192+5/64)=197
4^x=197*64/197
4^x=64
4^x=4^3
x=3