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why are the the x intercepts 0,-3 ??? I thought they should be -3,-3

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2 Answers

X intercepts are where the line crosses or touches the x axis thus y=0

for y=3(x+3) a straight line that crosses the x axis at only one point, so when you solve for x with y=0, x then equals -3 thus you get ordered pair (-3,0)

But what I think you wished for y=3(x+3)2

Again solve for x with y=0, 0/3=(x+3)(x+3)=x2+6x+9 solving the quadratic you get two equal solutions -3 and -3 which is of course only one actual solution so if you graph it you have a parabola that only touches but not crosses the x axis at the ordered pair (-3,0)

 

 

 

Remember the equation of a line is y=mx+b. Where m is the slop and b is the y intercept. By multiplying the 3 through the parentheses, the equation is now in the standard form y=mx+b. Now, you should be able to solve for the x and y intercepts.