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Ch. 2-4 continued. POD. Solve: 2y=3y-20 Ace Truck Rental charges $54 a day plus $.09 per mile. Roni’s Truck Rental charges $38 a day plus $.13 per mile. For how many miles will the cost of renting a truck for one day at Ace equal the cost at Roni’s ?.
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POD • Solve: 2y=3y-20 • Ace Truck Rental charges $54 a day plus $.09 per mile. Roni’s Truck Rental charges $38 a day plus $.13 per mile. For how many miles will the cost of renting a truck for one day at Ace equal the cost at Roni’s?
Identities & Equations with no solutions • Identity: an equation that is true for every value of the variable - example: 2x = 2x Solve: 10-8a = 2(5-4a) 10-8a = 2(5-4a) 10-8a = 10 – 8a +8a +8a 10 = 10 This is always true! Therefore it is an identity!
Example 2 8z-7=3z-7+5z 8z-7=8z-7 -8z -8z -7=-7 Combine like terms
Practice • 4(b-1)=-4+4b • 6y+9=3(2y+3)
When we have no solution… 6m – 5 = 7m+7-m 6m -5 = 6m +7 -6m -6m -5 = 7 Combine like terms -5 ≠ 7 therefore I have no solution
Example 2 Combine like terms 3(n-1) = 5n +3 -2n 3n -3 = 3n +3 -3n -3n -3 = 3 -3 ≠ 3 No Solution
Practice • 8(2f-3) = 4(4f-8) • 3(2f+4) = 2(3f -6)
Homework • Page 99 #’s 22-39