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Use intercepts to graph the linear equation - 2x + 7y= -21.x intercept y intercept step by step explanation

User David Go
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1 Answer

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Re- writing -2x + 7y = -21

7y = 2x -21

To get the x-intercept, we will substitute the value of y =0

0 = 2x - 21

collecting like terms and making x the subject of the formula

2x = 21

divide both sides by 2 (coefficient of x)

x = 21/2

x-intercept => (21/2, 0)

To get the y-intercept, we will substitute the value of x = 0

7y = 0 - 21

7y = -21

Divide both sides by 7 (coefficient of y)

y = -21/7

y = -3

y-intercept=> (0, -3)

User Craig Anderson
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