2nd part. Multiply both sides by s getting s^2-sy=5+y Then s^2-5=y+sy
So s^2-5=y(1+s) and (s^2-5)/(1+s)=y
Rearrange the equation
Root((a^2)+(7)^2)=z^2
to make a the subject.
rearrange theeqaution s-y=(5+y)/s
to make y the subject
find if
root((a^2)+(b^2))=a+b
is true for all values of a and b or some values of a and b or no vvalues of a and b