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Multi choice choose the rule for the table year 8 level maths

Multi choice choose the rule for the table year 8 level maths-example-1
User Gandalfml
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1 Answer

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17 votes

Answer:

second option, x + 2y = 3

Explanation:

The slope intercept form is y = mx + b

y = y coordinate

m = slope

x = x coordinate

b = y intercept

The y - intercept is when x = 0

In the table its shown that (0, 3), y = 3 so b = 3

The slope (gradient) is a number that describes both the direction and the steepness of the line.

slope = rise / run =
(y_(2) - y_(1) )/(x_(2) - x_(1) )

(x_1, y_1) = coordinates of first point in the line

(x_2, y_2) = coordinates of second point in the line

x is increasing by 1 (run)

y is decreasing by 2 (rise)

rise / run = -2 / 1 = -2

so the slope is -2

our slope intercept equation is, y = -2x + 3

Choice:

Some choice are in standard form so we need to convert to slope intercept

  • y = x + 3 is already in the correct form
  • 2x + y = 3 becomes y = -2x + 3

subtract 2x from both sides, 2x - 2x + y = 3 - 2x

  • x + 2y = 3 becomes y = -1/2x - 3/2

subtract x from both sides, x - x + 2y = 3 - x becomes 2y = 3 - x

divided both sides by 2, 2y / 2 = (3 - x) / 2

  • x - y = 0 becomes y = x

subtract x from both sides, x - x - y = 0 - x than switch signs

which option matches?!

THE SECOND ONE

User Criz
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