Respuesta :

Answer:

Step-by-step explanation:

the equation is  3-8*cos(x) = 7

plugging in 45°  to Cos  give  [tex]\sqrt{2}[/tex] / 2

then the equations looks like

3-8* ([tex]\sqrt{2}[/tex] / 2)  = y

3-4[tex]\sqrt{2}[/tex]  = y  

there is your answer... don't get rid of the square root.. that's an exact answer