If y=a+xb, where a and b are constants, and if y=1 when x=−1, and y=5 when x=−5, then a+b equals:
<spanclass=′latex−bold′>(A)</span>−1<spanclass=′latex−bold′>(B)</span>0<spanclass=′latex−bold′>(C)</span>1<spanclass=′latex−bold′>(D)</span>10<spanclass=′latex−bold′>(E)</span>11