Answer:
B
Step-by-step explanation:

Pumping iron: 10x+90=0
Fit for life: 15x+50=0
Set them equal to each other. 10x+90=15x+50. Solve for x. Subtract 50 from both sides, get 10x+40=15x, then subtract 10x from both sides, getting 40=5x. Divide 5 from both sides to isolate x, x=8. After 8 months the two gyms will cost the same.
Answer:
Only student 2
Step-by-step explanation:
a + b = 88 <span>
<span>
</span><span>ab = y
</span><span>
</span><span>a = 88 - b
</span><span>
</span><span>y = (88 - b)*b
</span>
<span>y = -b^2 + 88b
</span><span>
</span><span>Take the derivative and set equal to 0
</span><span>
</span><span>y' = -2b + 88 = 0
</span><span>
</span><span>2b = 88
</span>
<span>b = 44 </span></span>
<span><span>a=44</span></span>
<span><span> both numbers are 44</span></span>
Answer:
Step-by-step explanation:
I answered another one of your questions so I will not explain as much. ther are 12 inches in a foot and then 5280 feet in a mile so that's 1 ft/ 12 in and 1 mi/ 5280 ft. So the math is 20 in * 1 ft/ 12 in * 1 mi/ 5280 ft = .000315 mi.
In reference to the last one, do keep in mind "square" inches and whatnot mean you square things. so 1 ft/ 12 in becomes 1 ft^2/ 144 in^2. Just as a small heads up to what could be tricky.