triangle ABC has its coordinates at A(a, -1) , B(8,-1) , C(5,4). If the base is twice the

height, find a.

can anybody do me a favor on this problem...

thanks a lot

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- Dec 8th 2012, 08:47 PMrcsfind the value of a in coordinate
triangle ABC has its coordinates at A(a, -1) , B(8,-1) , C(5,4). If the base is twice the

height, find a.

can anybody do me a favor on this problem...

thanks a lot - Dec 9th 2012, 12:10 AMMarkFLRe: find the value of a in coordinate
If we assume the base lies along the line $\displaystyle y=-1$, then what is the vertical distance (the altitude of the triangle) from point $\displaystyle C$ to this line?

Once you find the altitude, then what are the $\displaystyle x$-coordinates of the two points on the base line whose distance from point $\displaystyle B$ is twice the altitude? - Dec 9th 2012, 12:15 AMBobPRe: find the value of a in coordinate
I suppose the base is intended to be AB, (but it depends on which way you choose to look at it, a badly worded question), so, since A and B have the same y coordinate, the base length will be the difference between their x coordinates.

Also, since A and B have the same y coordinate, it's easy to work out the height of the triangle.

All that's left is to say the base length is double the height and to solve the resulting equation. - Dec 9th 2012, 02:59 AMrcsRe: find the value of a in coordinate
- Dec 9th 2012, 03:03 AMMarkFLRe: find the value of a in coordinate
There is another solution as well, and both are easily found if you follow my suggestion above.