The first company charges $3.50 per cubic foot of rock and $80 for delivery. The second company charges $2.50 per cubic foot of rock and $120 for delivery. Which system of equations can be used to determine the value of the width, x, at which the cost of the two companies, y, is the same?

x = 40

Step-by-step explanation:

First company:

Charges = per cubic foot of rock fee + delivery fee

y = $3.50x + $80

Second company:

Charges = per cubic foot of rock fee + delivery fee

y = $2.50x + $120

Equate the charges of both companies

$3.50x + $80 = $2.50x + $120

3.50x - 2.50x = 120 - 80

x = 40

The cost of the two companies, y are equal when x = 40

2/3x + 7 = 29

step-by-step explanation:

two thirds = 2/3

plus a number = x

at least 29 = 29

there for you should get 2/3x + 7 = 29

make sure you have version 2.50

try looking in the very back of the book : )

step-by-step explanation:

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