Asked by math

Triangle abc is similar to triangle def, de=4, ab=x, ac=x+2, df= x+6
What does length ab equal?
Answered by Reiny
Did you make a sketch of the two triangles??
Fill in the corresponding data values.

<b>If triangles are similar, then their corresponding sides
are in the same ratio.</b>

Let me know what your opening equation is.
Answered by math 2.0
I did proportions and got x^2+2x=8

I don't remember if I can factor x^2+2x
Answered by Reiny
You were doing great so far.

x^2+2x=8 <------ a quadratic, put it in proper form.
x^2 + 2x - 8 = 0
(x + 4)(x - 2) = 0
x = -4 or x = 2, but x could not be negative, so x = 2
and AB = 2
Answered by math 2.0
ohhh okay thank you
Answered by Henry2
AB/DE = AC/DF.
x/4 = (x+2)/(x+4),
x^2 + 6x = 4x + 8,
x^2 + 2x -8 = 0,
(x-2)(x+4) = 0,
X = 2, and -4.
AB = X = 2.
We used the +value of X.