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Please Help Fast Algebra 1

Please Help Fast Algebra 1-example-1
User JillevdW
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1 Answer

6 votes

Answer:

The answer is B.

Explanation:

The question ask us to find an equation for the cost of a fill-up and a car wash. Firstly, we have to form 2 coordinates from the table and find the gradient :


m = (y2 - y1)/(x2 - x1)

Let Tank Size be x and Total Cost be y,

Any 2 coordinates,

Let (11,21.45) be (x1,y1) & (15,28.25) be (x2,y2),

m = (28.25-21.45)/(15-11)

= 6.8/4

= 1.7

You can form equation using slope-form, y = mx+b, then substitute m value and any coordinates into the equation :

Let m= 1.7 & (17,31.65),

y = mx + b

31.65 = 1.7(17) + b

31.65 - 1.7(17) = b

b = 2.75

y = 1.7x + 2.75

User Alexey Rodionov
by
4.1k points