Please explain how to do this.

Step-by-step explanation:

let the eqn be y = mx + b.

m = 200/(900 - 700) = 1

sub (700, 0):

0 = 700 + b

b = -700

therefore eqn is y = x - 700

Topic: coordinate geometry

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3x + 4y -25 =0 represents the amount of change sianna should recieve

no solution

step-by-step explanation:

there is not enough information in the problem to solve.