Answers:
bio = 258
sociology = 169
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Work Shown:
x = number of bio textbooks
y = number of sociology textbooks
x+y = 427 books sold total
y = x-89 since 89 less sociology textbooks were sold compared to bio
Apply substitution to get the following
x+y = 427
x+x-89 = 427 ... replace y with x-89
2x-89 = 427
2x = 427+89
2x = 516
x = 516/2
x = 258 bio textbooks were sold
y = x-89
y = 258-89
y = 169 sociology textbooks were sold
2, 6, 18, 54, 162, 486...
Start with the number 2.

And continue with that pattern from there.
Answer:
An equation for each situation, in terms of x
A = 35 + 3x
B = 80 + 2x
The interval of miles driven x, for which Company A is cheaper than Company B is 0 to 44.9 miles.
Step-by-step explanation:
Let A represent the amount Company A would charge if Piper drives x miles
Let B represent the amount Company B would charge if Piper drives x miles.
Company A charges an initial fee of $35 for the rental plus $3 per mile driven.
A= $35 + $3 × x
A = 35 + 3x
Company B charges an initial fee of $80 for the rental plus $2 per mile driven.
B = $80 + $2 × x
B = 80 + 2x
The interval of miles driven x, for which Company A is cheaper than Company B.
= A < B
35 + 3x < 80 + 2x
3x - 2x < 80 - 35
x < 45 miles
That is: any number of miles driven below 45 miles makes Company A cheaper than Company B
The interval of miles driven x, for which Company A is cheaper than Company B is 0 to 44.9 miles.
Answer:
3
Step-by-step explanation:
4x3=12
49.75
50%=.50
99.50 x .50 = 49.75