Ince DH=HF you set x+3=3y <span>GH=HE so 4x-5=2y+3 </span>
<span>This gives you a system and I solved by substitution so I got x alone in the first equation-> x=3y-3 </span> <span>then I plugged this x into the second equation so </span>
If you want to find cosP , since angles Z and P are 2 complementary angles then cosZ is the same as cosP so you say the cosP=sinZ=4/5 (property of 2 complement angles in a right triangle)