I have a problem with this question, Can any tell me if i did anything wrong in this question? and give me clues on how to proceed from where i left off

tan(32)=y/d

y=d*(tan(32)) Equation 1

tan(69)=(y+7.8)/d

y+7.8=d*tan(69)

y=d*(tan(69)) - 7.8 Equation 2

Sub equation 1 into equation 2

d*tan(32) = d*(tan(69)) - 7.8

That's where i'm stuck at the moment, i don't really know if my working out is correct, can anyone help me?

I'm trying to find "d" by the way