<span>b=12 ans. for the base.
Proof
168=12(2*12+4)/2
168=12(24+4)/2
168=12*28/2
168=336/2
168=168
I Hope this helps</span>
I think, I'd go with A) Always true. As 2 points is always the line. If you add third one, it will be collinear.
In order for the triangle to be isosceles, we have to set two lengths of the triangle equal to each other.
Let's take the lengths 5x-12 and x+20 and set them equal to each other.
5x - 12 = x + 20
Combine like terms by moving them over to their respective sides.
Subtract x from both sides of the equation.
4x - 12 = 20
Add 12 to both sides of the equation.
4x = 32
Divide both sides by 4.
x = 8
Check your answer by substituting.
5x - 12 = x + 20
5(8) - 12 = 8 + 20
40 - 12 = 28
28 = 28
Solution: x = 8
Quotient: 5x+5
Remainder: -5
We manipulate the given equation in order to solve for EC. We do this by cross multiplying.
The resulting equation will be:
EC = (4 x 3)/5
EC = 12/5 = 2.4
Additionally, the side-splitter theorem works for this problem since DE and AC are parallel to each other, therefore splitting the remaining two sides into proportional segments.
