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Find the y-intercept of the line: 9x + 3y = -18

(0,-6)


(0,6)


(-2,0)


(3,9)

1 Answer

3 votes

Answer:

(0,-6)

Explanation:

9x + 3y = -18

Solve for y to get equation in slope intercept form

( y = mx + b )

9x + 3y = -18

Subtract 9x from both sides

9x - 9x + 3y = -18 - 9x

3y = -9x - 18

Divide both sides by 3

3y/3 = y

-9x - 18 / 3 = -3x - 6

We're left with y = -3x - 6

The equation is now in y intercept form

y = mx + b where b = y intercept

-6 takes the spot of b therefore the y intercept would be at (0,-6)

User Lachlan Wetherall
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