Answer:
471.24
Step-by-step explanation:
-12 + 9y = -57
add 12 to both sides, 9y = -45
divide 9 from both sides to isolate the y
y = -5
<span>Tom:
time to </span>build a fence<span>= 4 hours; rate =1/4 job/hr.
tom &jack
</span>time to build a fence <span>= 3 hrs.; rate = 1/3 job/hr
</span><span>Jack :
time to </span>build a fence= x hrs ; rate = 1/x job/hr
<span>1/4 + 1/x = 1/3
3x + 12 = 4x
x=12 hrs. (Time for jack to build a fence )</span>
2 1/2. It contains a fraction and a whole number.