If a firm has $1000 par value bonds having 12 years to maturity and paying 9.5% coupon, with semi-annual payments,

what is bond's yield to maturity (market's required rate of return) if the bonds are selling for $1200

I know:

bond value formula

pv=1200

fv=1000

because it's semi annual:

n=12(2)=24

pmt=9500/2=4750

I don't know how to solve for r in a complex equation like this

please teach me how with work/ steps

thank you