Answer:
a=245 s=315
Step: Solve a+s=560 for a:
a+s=560
a+s=560(Add -s to both sides)
a=−s+560
Step: Substitute −s+560 for a in 8a+3s=2905:
8a+3s=2905
8(−s+560)+3s=2905
−5s+4480=2905(Simplify both sides of the equation)
−5s+4480=2905(Add -4480 to both sides)
−5s=−1575
−5s=−1575(Divide both sides by -5)
s=315
Step: Substitute 315 for s in a=−s+560:
a=−s+560
a=−315+560
a=245
