If p SQUARE + q SQUARE + r SQUARE = 20 and pq + qr + rs = 15, then the

1.	If p SQUARE + q SQUARE + r SQUARE = 20 and pq + qr + rs = 15, then the value of p + q + r is
Answer» ANSWER: $\textsf{The value of p+q+r is $5\sqrt{2}$}$ Step-by-step EXPLANATION: $\textsf{Given:}$ $\mathsf{p^2+q^2+r^2=20}$ $\mathsf{pq+qr+rp=15}$ $\textsf{Using the algebraic identity}$ $\boxed{\mathsf{(a+b+c)^2=a^2+b^2+c^2+2(ab+bc+ca)}}$ $\mathsf{(p+q+r)^2=p^2+q^2+r^2+2(pq+qr+rp)}$ $\mathsf{(p+q+r)^2=20+2(15)}$ $\mathsf{(p+q+r)^2=20+30}$ $\mathsf{(p+q+r)^2=50}$ $\mathsf{p+q+r=\sqrt{50}}$ $\implies\boxed{\mathsf{p+q+r=5\sqrt{2}}}$