Answer:
I believe its Calculus
Step-by-step explanation:
The package weighs 30 ounces.
Step-by-step explanation:
Mailbox Plus charges;
Charges per ounce = $0.25
Let,
x be the number of ounces.
M(x)=5+0.25x
United packges charges;
Charges per ounce = $0.35
U(x) = 2+0.35x
Cost will be same when the functions are equal;
M(x) = U(x)

Dividing both sides by 0.10

The package weighs 30 ounces.
Keywords: functions, division
Learn more about division at:
#LearnwithBrainly
<h3>
Answer: Choice D) 22.5</h3>
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Explanation:
x = length of BC
AC = AB+BC
AC = 6 + x
CE = CD+DE
CE = 22+8
CE = 30
Triangles ACE and BCD are similar triangles (can be proven by the AA similarity theorem due to the fact that AE || BD)
Therefore the corresponding sides are proportional letting us set up the proportion below
AC/BC = CE/CD
(6+x)/x = 30/22 .... substitution
22(6+x) = 30x ... cross multiply
132+22x = 30x
132 = 30x-22x ..... subtract 22x from both sides
132 = 8x
8x = 132
x = 132/8 .... divide both sides by 8
x = 16.5
Now use this to find the length of AC
AC = 6+x
AC = 6+16.5
AC = 22.5
Answer:
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