<span>The answer to this question would be: A. the number of adults
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In this question, there are 4 times as many students as adults going on the trip. If we put it into a function where s= student and a=adult, then we could get one equation:<span>
1. s=4a
</span><span>
Each student ticket cost $2 and each adult ticket cost $4. The total cost of the trip is $144. We also can get one equation for this
2. 2s+ 4a= 144
If you put the first equation into the second, you will get:
</span>2s+4a= 144
2(4a)+4a= 144
The function is already similar with <span>2(4x)+4x but it uses a instead of x. Then x = a = number of adult</span>
ANSWER

EXPLANATION
The given equation is:

Group similar terms to obtain:

Simplify similar terms,

Divide both sides by -2.5


Answer:
f(x) = -5/9 x + 5 1/9
Step-by-step explanation:
f(2)=4 and f(−7)=9 means the line pass through (2,4) and (- 7,9)
f(x) = mx + b
m = (y-y') / (x-x') = (9 - 4) / (- 7 - 2) = - 5/9
for (2,4) : b = f(x) - mx = y - mx = 4 - (- 5/9) x 2 = 4 + 10/9 = 46/9 = 5 1/9
f(x) = -5/9 x + 5 1/9
check for (-7, 9) f(-7) = (-5/9) * (-7) + 5 1/9 = 35/9 + 46/9 = 81/9 = 9